鸿蒙入门指南，小白速来！从萌新到高手，怎样快速掌握鸿蒙开发？【课程入口】
目录：
1. 鸿蒙版图片裁剪功能，效果如下:
首页
图片裁剪区域:
裁剪结果：
2.Java代码实现如下:
package com.example.javahm9.slice;
import com.example.javahm9.ResourceTable;
import com.example.javahm9.util.CropImage;
import ohos.aafwk.ability.AbilitySlice;
import ohos.aafwk.content.Intent;
import ohos.agp.colors.RgbColor;
import ohos.agp.components.Button;
import ohos.agp.components.Component;
import ohos.agp.components.Text;
import ohos.agp.components.element.ShapeElement;
public class MainAbilitySlice extends AbilitySlice {
//定义一个图片
Component image;
//定义一个文本
Text text;
@Override
public void onStart(Intent intent) {
super.onStart(intent);
super.setUIContent(ResourceTable.Layout_ability_main);
//获取图片对象对应的component
image = findComponentById(ResourceTable.Id_result_image);
/*
* 如果接收的cropFlag为true
* 处理剪裁后的图片
* 否则跳过
*/
if(intent.getBooleanParam("cropFlag",false)){
handleCrop(intent);
}
/* 自定义--获取文本对象对应的component
* 根据intent里面的cropStatus来显示不同的文本
* 0表示未接收到数据
* 1表示剪裁取消
* 2表示剪裁成功 有数据
*/
text = (Text) findComponentById(ResourceTable.Id_text);
if(intent.getIntParam("cropStatus",0) == 0){
text.setText("欢迎使用");
}else if(intent.getIntParam("cropStatus",0) == 1){
text.setText("剪裁取消");
}else if(intent.getIntParam("cropStatus",0) == 2){
text.setText("剪裁成功");
}
//获取button对象对应的component
Button button = (Button) findComponentById(ResourceTable.Id_button);
// 设置button的属性及背景
ShapeElement background = new ShapeElement();
// background.setRgbColor(new RgbColor(125, 125, 255));
background.setCornerRadius(25);
// button.setBackground(background);
if (button != null) {
// 绑定点击事件
button.setClickedListener(new Component.ClickedListener() {
public void onClick(Component v) {
begincrop();
}
});
}
}
public void begincrop(){
CropImage.activity()
.setContext(this)
.setSource(ResourceTable.Media_a9)
.setBundleName("com.example.javahm9")
.setAbilityName("com.example.javahm9.MainAbility")
.setRequset_code(1234)
.start(super.getAbility(),this);
}
//处理剪裁结果
private void handleCrop(Intent result) {
int resultImg = result.getIntParam("resultImg",0);
int result_code = result.getIntParam("result_code" , 0);
if(resultImg != 0){
CropImage.handleImage(result_code , image);
}
}
@Override
public void onActive() {
super.onActive();
}
@Override
public void onForeground(Intent intent) {
super.onForeground(intent);
}
}
3.裁剪工具类实现
package com.example.javahm9.util;
import ohos.aafwk.ability.Ability;
import ohos.aafwk.ability.AbilitySlice;
import ohos.aafwk.content.Intent;
import ohos.agp.components.Component;
import ohos.agp.render.Canvas;
import ohos.agp.render.Paint;
import ohos.agp.render.PixelMapHolder;
import ohos.app.Context;
import ohos.media.image.PixelMap;
import ohos.utils.net.Uri;
/**
* @Author 李欣
* <p>
* 此类是一个工具类
* <p>
* 此类是面向于用户的 面向于MainAbilitySlice的
* <p>
* 此类提供设置一些参数的功能，提供了页面跳转，跳转到CropImageActivity的方法，有一些属性暂时用不到。
*/
public final class CropImage {
//存一个context
private static Context mContext;
//图片资源文件
private static int msource;
//裁减结果
public static final boolean CROPFLAG = true;
//空的构造器
private CropImage() {
}
//内部类初始化
public static ActivityBuilder activity() {
return new ActivityBuilder(null , null , null , 0);
}
/**
* 这个方法对传进来的 component进行操作
* 给这个空的component增加图片 旋转等等
* @param result 一个参数用来判断返回的结果 以及如何处理
* @param component 对这个component进行操作
*/
public static void handleImage(int result, Component component) {
//203表示裁剪成功（203为自定义的数字）
if (result == 203) {
//获得原始位图
PixelMap pixelMap = BitmapUtils.getOriginalPixelMap(mContext , msource).get();
//创建屏幕工具类 获得屏幕的宽度
CropWindowHandler windowHandler = new CropWindowHandler(mContext);
/**
* 缩放指数 原始的图片的缩放大小
* 数值为原始图片的宽度（pixelMap.getImageInfo().size.width）除以屏幕的宽度（windowHandler.getWindowWidth()） 的倒数
*/
float ratio = (float) windowHandler.getWindowWidth()/(float) pixelMap.getImageInfo().size.width;
//获得裁剪后的位图
PixelMap cropped = CropOverlayView.getCroppedPixelMap();
PixelMapHolder pixelMapHolder = new PixelMapHolder(cropped);
//创建bitmaputils工具类，获得位图相关数据
BitmapUtils bitmapUtils = new BitmapUtils(mContext, cropped, 400, msource);
/**
* 创建画位图的方法
* 获取到之前的点击动作数组 这样就可以获得到具体最终的图片的方向
* 并且依次按照图片方向进行旋转
*/
Component.DrawTask drawTask = new Component.DrawTask() {
@Override
public void onDraw(Component component, Canvas canvas) {
//获得行为动作
int[] action = CropImageView.getActionResult();
//获得动作数目
int actionIndex = CropImageView.getActionIndexResult();
//循环执行旋转、翻转动作
for (int i = 0; i < actionIndex; i++) {
if (action[i] == 1) {
//rotate图像
canvas.rotate(90, bitmapUtils.getRealPixelMapWidth() / 2 * ratio, bitmapUtils.getRealPixelMapHeight() / 2 * ratio);
} else if (action[i] == 2) {
//水平翻转
//向下移动高度
canvas.translate(bitmapUtils.getRealPixelMapWidth() * ratio, 0);
//向y轴负方向缩放一倍
canvas.scale(-1f, 1f);
} else if (action[i] == 3) {
//垂直翻转
//向下移动高度
canvas.translate(0, bitmapUtils.getRealPixelMapHeight() * ratio);
//向y轴负方向缩放一倍
canvas.scale(1f, -1f);
}
}
//按照原来的比例进行缩放
canvas.scale(ratio , ratio);
//画图
canvas.drawPixelMapHolder(pixelMapHolder, 200, 230, new Paint());
}
};
//为component增加drawtask方法
component.addDrawTask(drawTask);
}
}
public static PixelMap getCroppedPixelMap(){
return CropOverlayView.getCroppedPixelMap();
}
public static final class ActivityBuilder {
//设置图片的Uri
private final Uri mSource;
//需要跳转回的bundle的名字
private String bundleName;
//需要跳转回的Ability的名字
private String abilityName;
//request_code
private int request_code;
//初始化 记录一些信息
private ActivityBuilder(Uri source , String bundle , String ability , int request) {
mSource = source;
bundleName = bundle;
abilityName = ability;
request_code = request;
}
//返回一个intent
public Intent getIntent(Context context) {
return getIntent(context, CropImageActivity.class);
}
//返回一个intent 用来实现页面跳转
public Intent getIntent(Context context, Class<?> cls) {
Intent intent = new Intent();
intent.setParam("source", msource);
if(bundleName != null){
intent.setParam("bundleName" , bundleName);
}
if(abilityName != null){
intent.setParam("abilityName" , abilityName);
}
if(request_code != 0){
intent.setParam("request_code" , request_code);
}
return intent;
}
//页面跳转
public void start(Ability ability, AbilitySlice abilitySlice) {
start(ability, abilitySlice, request_code);
}
//页面跳转
public void start(Ability ability, AbilitySlice abilitySlice, int requestCode) {
//给crop添加操作
AbilitySlice cropImageAbilitySlice = new CropImageActivity();
abilitySlice.presentForResult(cropImageAbilitySlice, getIntent(ability), requestCode);
}
//设置资源图片，被裁减的图片的id
public ActivityBuilder setSource(int source) {
msource = source;
return this;
}
//设置context
public ActivityBuilder setContext(Context context) {
mContext = context;
return this;
}
//设置需要跳转回的bundle名字
public ActivityBuilder setBundleName(String s){
bundleName = s;
return this;
}
//设置需要跳转回的ability名字
public ActivityBuilder setAbilityName(String s){
abilityName = s;
return this;
}
//设置需要跳转回时的code
public ActivityBuilder setRequset_code(int i){
request_code = i;
return this;
}
}
}
package com.example.javahm9.util;
import ohos.aafwk.ability.AbilitySlice;
import ohos.aafwk.content.Intent;
import ohos.aafwk.content.Operation;
import ohos.agp.colors.RgbColor;
import ohos.agp.components.Button;
import ohos.agp.components.Component;
import ohos.agp.components.DependentLayout;
import ohos.agp.components.element.ShapeElement;
import ohos.agp.utils.RectFloat;
import ohos.bundle.AbilityInfo;
import ohos.media.image.PixelMap;
import static ohos.agp.components.ComponentContainer.LayoutConfig.MATCH_PARENT;
/**
* @Author 李欣
*
* 此类为裁剪功能实现的主要页面
*
* 此页面上显示了一些功能性的button
* 还有被裁减图片以及裁剪框
*/
public class CropImageActivity extends AbilitySlice {
//定义此slice的Dependent布局
private DependentLayout myLayout = new DependentLayout(this);
//被裁减图片
private Component mPicture;
//被裁减图片的位图
private PixelMap mPixelMap;
//位图工具类
private BitmapUtils mBitmapUtils;
//屏幕工具类
private CropWindowHandler mCropWindowHandler;
//裁剪框
private Component mCropBound;
//裁剪框工具类
private CropOverlayView mCropOverlayView;
//图片资源
private int mSource;
//图片上边距
private final int topIndex = 400;
//图片工具类
private CropImageView mCropImageView;
//裁减结果的矩阵
public static RectFloat croppedRectFloat;
//裁减结果的pixelmap
public static PixelMap croppedPixelMap;
@Override
public void onStart(Intent intent) {
super.onStart(intent);
//创建本slice的布局文件
DependentLayout.LayoutConfig config = new DependentLayout.LayoutConfig(MATCH_PARENT, MATCH_PARENT);
//设置默认竖屏
setDisplayOrientation(AbilityInfo.DisplayOrientation.PORTRAIT);
//设置布局的背景
myLayout.setLayoutConfig(config);
ShapeElement element = new ShapeElement();
element.setRgbColor(new RgbColor(255, 255, 255));
myLayout.setBackground(element);
//设置button,image等
setupViews(intent);
//加载裁剪框、背景图片等等
loadInput();
//加载布局
super.setUIContent(myLayout);
}
//按钮和图片初始化
private void setupViews(Intent intent) {
buttonInit(intent);
imageInit(intent);
}
//按钮初始化
private void buttonInit(Intent intent) {
//创建button
Button cancel = cancelButton(intent);
Button rotate = rotateButton();
// Button horfilp = horizontalFilpButton();
// Button verfilp = verticalFilpButton();
Button crop = cropButton(intent);
//将button添加到布局
myLayout.addComponent(cancel);
myLayout.addComponent(rotate);
// myLayout.addComponent(horfilp);
// myLayout.addComponent(verfilp);
myLayout.addComponent(crop);
}
//取消按钮
private Button cancelButton(Intent intent) {
//创建取消button
Button cancel = new Button(this);
//为button增加布局条件
DependentLayout.LayoutConfig cancelLayoutConfig = new DependentLayout.LayoutConfig();
cancelLayoutConfig.setMargins(140, 50, 0, 0);
cancelLayoutConfig.addRule(DependentLayout.LayoutConfig.ALIGN_TOP);
cancelLayoutConfig.addRule(DependentLayout.LayoutConfig.ALIGN_PARENT_LEFT);
//设置背景颜色
cancel.setLayoutConfig(cancelLayoutConfig);
ShapeElement cancelElement = new ShapeElement();
cancelElement.setRgbColor(new RgbColor(155, 155, 155));
cancelElement.setCornerRadius(25);
cancel.setBackground(cancelElement);
//设置文本
cancel.setText("取消");
cancel.setTextSize(55);
cancel.setHeight(180);
cancel.setWidth(220);
//绑定点击方法
cancel.setClickedListener(new Component.ClickedListener() {
public void onClick(Component v) {
//为按钮绑定方法
cancel(intent);
}
});
return cancel;
}
//旋转按钮
private Button rotateButton() {
//创建旋转button
Button rotate = new Button(this);
//为button增加布局条件
DependentLayout.LayoutConfig rotateLayoutConfig = new DependentLayout.LayoutConfig();
rotateLayoutConfig.setMargins(500, 50, 0, 0);
rotateLayoutConfig.addRule(DependentLayout.LayoutConfig.ALIGN_TOP);
rotateLayoutConfig.addRule(DependentLayout.LayoutConfig.ALIGN_PARENT_LEFT);
rotate.setLayoutConfig(rotateLayoutConfig);
//设置背景颜色
ShapeElement rotateElement = new ShapeElement();
rotateElement.setRgbColor(new RgbColor(255, 228, 181));
rotateElement.setCornerRadius(25);
rotate.setBackground(rotateElement);
//设置文本
rotate.setText("旋转");
rotate.setTextSize(55);
rotate.setHeight(180);
rotate.setWidth(220);
//绑定点击方法
rotate.setClickedListener(new Component.ClickedListener() {
public void onClick(Component v) {
rotate();
}
});
return rotate;
}
//水平翻转按钮
private Button horizontalFilpButton() {
//创建翻转button
Button filp = new Button(this);
//为button增加布局条件
DependentLayout.LayoutConfig filpLayoutConfig = new DependentLayout.LayoutConfig();
filpLayoutConfig.setMargins(0, 50, 300, 0);
filpLayoutConfig.addRule(DependentLayout.LayoutConfig.ALIGN_TOP);
filpLayoutConfig.addRule(DependentLayout.LayoutConfig.ALIGN_PARENT_RIGHT);
//设置背景颜色
filp.setLayoutConfig(filpLayoutConfig);
ShapeElement filpElement = new ShapeElement();
filpElement.setRgbColor(new RgbColor(180, 238, 180));
filpElement.setCornerRadius(25);
filp.setBackground(filpElement);
//设置文本
filp.setText("horFilp");
filp.setTextSize(40);
filp.setHeight(85);
filp.setWidth(220);
//绑定点击方法
filp.setClickedListener(new Component.ClickedListener() {
public void onClick(Component v) {
horizontalFlip();
}
});
return filp;
}
//垂直翻转按钮
private Button verticalFilpButton() {
//创建翻转button
Button filp = new Button(this);
//为button增加布局条件
DependentLayout.LayoutConfig filpLayoutConfig = new DependentLayout.LayoutConfig();
filpLayoutConfig.setMargins(0, 145, 300, 0);
filpLayoutConfig.addRule(DependentLayout.LayoutConfig.ALIGN_TOP);
filpLayoutConfig.addRule(DependentLayout.LayoutConfig.ALIGN_PARENT_RIGHT);
//设置背景颜色
filp.setLayoutConfig(filpLayoutConfig);
ShapeElement filpElement = new ShapeElement();
filpElement.setRgbColor(new RgbColor(180, 238, 180));
filpElement.setCornerRadius(25);
filp.setBackground(filpElement);
//设置文本
filp.setText("verFilp");
filp.setTextSize(40);
filp.setHeight(85);
filp.setWidth(220);
//绑定点击方法
filp.setClickedListener(new Component.ClickedListener() {
public void onClick(Component v) {
verticalFlip();
}
});
return filp;
}
//裁剪按钮
private Button cropButton(Intent intent) {
//创建裁剪button
Button crop = new Button(this);
//为button增加布局条件
DependentLayout.LayoutConfig cropLayoutConfig = new DependentLayout.LayoutConfig();
cropLayoutConfig.setMargins(820, 50, 0, 0);
cropLayoutConfig.addRule(DependentLayout.LayoutConfig.ALIGN_TOP);
cropLayoutConfig.addRule(DependentLayout.LayoutConfig.ALIGN_PARENT_LEFT);
//设置背景颜色
crop.setLayoutConfig(cropLayoutConfig);
ShapeElement cropElement = new ShapeElement();
cropElement.setRgbColor(new RgbColor(0, 125, 155));
cropElement.setCornerRadius(25);
crop.setBackground(cropElement);
//设置文本
crop.setText("裁剪");
crop.setTextSize(55);
crop.setHeight(180);
crop.setWidth(220);
//绑定点击方法
crop.setClickedListener(new Component.ClickedListener() {
public void onClick(Component v) {
crop(intent);
}
});
return crop;
}
//图片初始化
private void imageInit(Intent intent) {
//获得图片的id
int source = intent.getIntParam("source", 0);
mSource = source;
//根据图片id获取pixelmap
PixelMap pixelMapOriginal = BitmapUtils.getOriginalPixelMap(this, mSource).get();
mPixelMap = pixelMapOriginal;
//创建bitmaputils工具类，获得位图相关数据
BitmapUtils bitmapUtils = new BitmapUtils(this , mPixelMap ,topIndex , mSource );
//创建cropwindowhandler工具类，获得windows相关数据
CropWindowHandler cropWindowHandler = new CropWindowHandler(this);
//创建图片工具类，用来获得图片
mCropImageView = new CropImageView(mPixelMap , this , mSource , topIndex);
//获取展示图片的component
mPicture = mCropImageView.getmPicture();
//计算图片的位置，使得图片居中显示，计算出图片距离屏幕左边的空白
int margin = cropWindowHandler.getWindowWidth()/2 - bitmapUtils.getPixelMapWidth()/2;
//给mPicture增加布局
DependentLayout.LayoutConfig componentLayoutConfig = new DependentLayout.LayoutConfig();
componentLayoutConfig.setMargins(0, topIndex, 0, 0);//边距
mPicture.setLayoutConfig(componentLayoutConfig);
//将图片加入布局
myLayout.addComponent(mPicture);
}
//初始化工具类，加载裁剪框等等
private void loadInput() {
//创建位图工具类
mBitmapUtils = new BitmapUtils(this, mPixelMap, 400, mSource);
//创建屏幕工具类
mCropWindowHandler = new CropWindowHandler(this);
//创建裁剪框的工具类
mCropOverlayView = new CropOverlayView(this, mBitmapUtils, mCropWindowHandler);
//获得裁剪框
mCropBound = mCropOverlayView.getmCropBound();
//将裁剪框加入布局文件
myLayout.addComponent(mCropBound);
}
//取消裁剪方法
private void cancel(Intent intentOriginal) {
Intent intent = new Intent();
//增加裁剪状态及结果
intent.setParam("cropFlag", !CropImage.CROPFLAG);
intent.setParam("cropStatus", 1);
// 通过Intent中的OperationBuilder类构造operation对象，指定设备标识（空串表示当前设备）、应用包名、Ability名称
Operation operation = new Intent.OperationBuilder()
.withDeviceId("")
.withBundleName(intentOriginal.getStringParam("bundleName"))
.withAbilityName(intentOriginal.getStringParam("abilityName"))
.build();
// 把operation设置到intent中
intent.setOperation(operation);
//跳转
startAbility(intent);
}
//图片旋转的方法
private void rotate(){
//图片旋转
mCropImageView.rotateOnce();
//裁剪框旋转
mCropOverlayView.rotateOnce();
}
//图片水平翻转的方法
private void horizontalFlip(){
//图片翻转
mCropImageView.horizontalFilp();
//裁剪框翻转
mCropOverlayView.horizontalFilpOnce();
}
//图片垂直翻转的方法
private void verticalFlip(){
mCropImageView.verticalFilp();
//裁剪框翻转
mCropOverlayView.verticalFilpOnce();
}
//成功裁剪方法
private void crop(Intent intentOriginal) {
//计算裁减后的pixelmap并存放于cropoverlayview中
mCropOverlayView.croppedPixel(this);
//显示到MainActivity
Intent intent = new Intent();
//增加裁剪状态及结果
intent.setParam("cropFlag", CropImage.CROPFLAG);
intent.setParam("cropStatus", 2);
intent.setParam("result_code" , 203);
RectFloat cropRect = mCropOverlayView.getmCropRect();
//塞入裁剪结果
intent.setParam("resultImg", mSource);
croppedRectFloat = mCropOverlayView.getmCropRect();
croppedPixelMap = mPixelMap;
// 通过Intent中的OperationBuilder类构造operation对象，指定设备标识（空串表示当前设备）、应用包名、Ability名称
Operation operation = new Intent.OperationBuilder()
.withDeviceId("")
.withBundleName(intentOriginal.getStringParam("bundleName"))
.withAbilityName(intentOriginal.getStringParam("abilityName"))
.build();
// 把operation设置到intent中
intent.setOperation(operation);
//跳转
startAbility(intent);
}
@Override
protected void onStop() {
super.onStop();
}
}
作者：六合李欣
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