http://blog.csdn.net/hmg25/article/details/6574575
android原生自带的桌面文件夹样式及其简单,没有iphone那种可以显示文件夹内文件图标缩略图的功能,今天我们来简单的实现一个。
效果如下:
从launcher源码中很容易变可以看出需要修改的文件,主要修改FolderIcon.java这个文件。修改后的代码如下:
- public class FolderIcon extends BubbleTextView implements DropTarget {
- private UserFolderInfo mInfo;
- private Launcher mLauncher;
- private Drawable mCloseIcon;
- private Drawable mOpenIcon;
- // add by hmg for FolderIcon {
- private IconCache mIconCache;
- private static final int ICON_COUNT = 4; //可显示的缩略图数
- private static final int NUM_COL = 2; // 每行显示的个数
- private static final int PADDING = 1; //内边距
- private static final int MARGIN = 7; //外边距
- // add by hmg for FolderIcon }
- public FolderIcon(Context context, AttributeSet attrs) {
- super(context, attrs);
- mIconCache = ((LauncherApplication) mContext.getApplicationContext())
- .getIconCache();
- }
- public FolderIcon(Context context) {
- super(context);
- mIconCache = ((LauncherApplication) mContext.getApplicationContext())
- .getIconCache();
- }
- static FolderIcon fromXml(int resId, Launcher launcher, ViewGroup group,
- UserFolderInfo folderInfo) {
- FolderIcon icon = (FolderIcon) LayoutInflater.from(launcher).inflate(
- resId, group, false);
- // final Resources resources = launcher.getResources();
- // Drawable d = resources.getDrawable(R.drawable.ic_launcher_folder);
- // icon.mCloseIcon = d;
- // icon.mOpenIcon =
- // resources.getDrawable(R.drawable.ic_launcher_folder_open);
- // icon.setCompoundDrawablesWithIntrinsicBounds(null, d, null, null);
- icon.setText(folderInfo.title);
- icon.setTag(folderInfo);
- icon.setOnClickListener(launcher);
- icon.mInfo = folderInfo;
- icon.mLauncher = launcher;
- icon.updateFolderIcon(); //更新图标
- folderInfo.setFolderIcon(icon); //设置FolderIcon
- return icon;
- }
- // add by hmg25 for FolderIcon {
- /**
- * Author : hmg25 Version: 1.0 Description : 更新FolderIcon显示的文件缩略图
- */
- public void updateFolderIcon() {
- float x, y;
- final Resources resources = mLauncher.getResources();
- Bitmap closebmp = BitmapFactory.decodeResource(resources,
- R.drawable.icon_folder); //获取FolderIcon关闭时的背景图
- Bitmap openbmp = BitmapFactory.decodeResource(resources,
- R.drawable.icon_folder_open); //获取FolderIcon打开时的背景图
- int iconWidth = closebmp.getWidth(); //icon的宽度
- int iconHeight = closebmp.getHeight();
- Bitmap folderclose = Bitmap.createBitmap(iconWidth, iconHeight,
- Bitmap.Config.ARGB_8888);
- Bitmap folderopen = Bitmap.createBitmap(iconWidth, iconHeight,
- Bitmap.Config.ARGB_8888);
- Canvas canvas = new Canvas(folderclose);
- canvas.drawBitmap(closebmp, 0, 0, null); //绘制背景
- Matrix matrix = new Matrix(); // 创建操作图片用的Matrix对象
- float scaleWidth = (iconWidth - MARGIN * 2) / NUM_COL - 2 * PADDING; //计算缩略图的宽(高与宽相同)
- float scale = (scaleWidth / iconWidth); // 计算缩放比例
- matrix.postScale(scale, scale); // 设置缩放比例
- for (int i = 0; i < ICON_COUNT; i++) {
- if (i < mInfo.contents.size()) {
- x = MARGIN + PADDING * (2 * (i % NUM_COL) + 1) + scaleWidth
- * (i % NUM_COL);
- y = MARGIN + PADDING * (2 * (i / NUM_COL) + 1) + scaleWidth
- * (i / NUM_COL);
- ShortcutInfo scInfo = (ShortcutInfo) mInfo.contents.get(i);
- Bitmap iconbmp = scInfo.getIcon(mIconCache); //获取缩略图标
- Bitmap scalebmp = Bitmap.createBitmap(iconbmp, 0, 0, iconWidth,
- iconHeight, matrix, true);
- canvas.drawBitmap(scalebmp, x, y, null);
- }
- }
- mCloseIcon = new FastBitmapDrawable(folderclose); //将bitmap转换为Drawable
- setCompoundDrawablesWithIntrinsicBounds(null, mCloseIcon, null, null);
- canvas = new Canvas(folderopen);
- canvas.drawBitmap(folderclose, 0, 0, null);
- canvas.drawBitmap(openbmp, 0, 0, null);
- mOpenIcon = new FastBitmapDrawable(folderopen); //绘制open图片
- }
- // add by hmg25 for FolderIcon }
- public boolean acceptDrop(DragSource source, int x, int y, int xOffset,
- int yOffset, DragView dragView, Object dragInfo) {
- final ItemInfo item = (ItemInfo) dragInfo;
- final int itemType = item.itemType;
- return (itemType == LauncherSettings.Favorites.ITEM_TYPE_APPLICATION || itemType == LauncherSettings.Favorites.ITEM_TYPE_SHORTCUT)
- && item.container != mInfo.id;
- }
- public Rect estimateDropLocation(DragSource source, int x, int y,
- int xOffset, int yOffset, DragView dragView, Object dragInfo,
- Rect recycle) {
- return null;
- }
- public void onDrop(DragSource source, int x, int y, int xOffset,
- int yOffset, DragView dragView, Object dragInfo) {
- ShortcutInfo item;
- if (dragInfo instanceof ApplicationInfo) {
- // Came from all apps -- make a copy
- item = ((ApplicationInfo) dragInfo).makeShortcut();
- } else {
- item = (ShortcutInfo) dragInfo;
- }
- mInfo.add(item);
- LauncherModel.addOrMoveItemInDatabase(mLauncher, item, mInfo.id, 0, 0,
- 0);
- updateFolderIcon(); //拖拽放入时更新
- }
- public void onDragEnter(DragSource source, int x, int y, int xOffset,
- int yOffset, DragView dragView, Object dragInfo) {
- setCompoundDrawablesWithIntrinsicBounds(null, mOpenIcon, null, null);
- }
- public void onDragOver(DragSource source, int x, int y, int xOffset,
- int yOffset, DragView dragView, Object dragInfo) {
- }
- public void onDragExit(DragSource source, int x, int y, int xOffset,
- int yOffset, DragView dragView, Object dragInfo) {
- setCompoundDrawablesWithIntrinsicBounds(null, mCloseIcon, null, null);
- }
- }
将文件拖拽进入文件夹时响应FolderIcon中的onDrop,所以添加updateFolderIcon();
以上代码可以实现将图标拖拽进文件夹时实时更新缩略图显示,还没有对拖拽出文件夹时更新显示,所以还需要修改其他地方。跟踪代码可以看出拖拽离开文件夹时响应UserFolder中方法onDropCompleted,需要修改UserFolder.java:
- public void onDropCompleted(View target, boolean success) {
- if (success) {
- ShortcutsAdapter adapter = (ShortcutsAdapter)mContent.getAdapter();
- adapter.remove(mDragItem);
- ((UserFolderInfo)mInfo).mFolderIcon.updateFolderIcon(); //add by hmg25 拖拽离开时更新
- }
- }
- ublic void onDrop(DragSource source, int x, int y, int xOffset, int yOffset,
- DragView dragView, Object dragInfo) {
- ShortcutInfo item;
- if (dragInfo instanceof ApplicationInfo) {
- // Came from all apps -- make a copy
- item = ((ApplicationInfo)dragInfo).makeShortcut();
- } else {
- item = (ShortcutInfo)dragInfo;
- }
- ((ShortcutsAdapter)mContent.getAdapter()).add(item);
- LauncherModel.addOrMoveItemInDatabase(mLauncher, item, mInfo.id, 0, 0, 0);
- ((UserFolderInfo)mInfo).mFolderIcon.updateFolderIcon(); //add by hmg25 将文件直接拖拽到打开的文件夹更新
从以上代码可以看出为了传递FolderIcon对象,所以我们还需要为UserFolderInfo添加一个mFolderIcon成员,修改UserFolderInfo.java:
- protected FolderIcon mFolderIcon = null; //add by hmg25 for Folder
- //add by hmg25 for Folder {
- void setFolderIcon(FolderIcon icon)
- {
- mFolderIcon=icon;
- }
- //add by hmg25 for Folder }
以上代码是在android2.2, 480*320下测试的,其他分辨率的可以修改
private static final int ICON_COUNT = 4; //可显示的缩略图数
private static final int NUM_COL = 2; // 每行显示的个数
private static final int PADDING = 1; //内边距
private static final int MARGIN = 7; //外边距
的值。