寒假学习8

Android Studio : Button

MainActivity.java

package com.example.myapplicationfirst;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {

    private Button mBtnTextView;
    private Button mBtnButton;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mBtnTextView = findViewById(R.id.btn_textview);
        mBtnTextView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //跳转到TextView演示界面
                Intent intent = new Intent(MainActivity.this,TextViewActivity.class);
                startActivity(intent);
            }
        });

        mBtnButton = findViewById(R.id.btn_button);
        mBtnButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //跳转到TextView演示界面
                Intent intent = new Intent(MainActivity.this, ButtonActivity.class);
                startActivity(intent);
            }
        });
    }
}

res > layout > activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <Button
        android:id="@+id/btn_textview"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="TextView"/>

    <Button
        android:id="@+id/btn_button"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Button"/>


</LinearLayout>

BottonActivity.java

package com.example.myapplicationfirst;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

public class ButtonActivity extends AppCompatActivity {

    private Button mBtn3;
    private TextView mTb1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_button);
        mBtn3 = findViewById(R.id.btn_3);
        mBtn3.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(ButtonActivity.this,"点击成功",Toast.LENGTH_SHORT).show();
            }
        });

        mTb1 = findViewById(R.id.tb_1);
        mTb1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(ButtonActivity.this,"点击成功",Toast.LENGTH_SHORT).show();
            }
        });
    }

    public void ShowToast(View view){
        Toast.makeText(this,"点击成功",Toast.LENGTH_SHORT).show();
    }
}

res > layout > activity_button.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="20dp">

    <Button
    android:id="@+id/btn_1"
    android:layout_width="match_parent"
    android:layout_height="50dp"
    android:text="按钮1"
    android:textSize="20sp"
    android:textColor="#EE0000"
    android:background="#11FF41"
    android:layout_marginTop="20dp"
        android:onClick="ShowToast"/>

    <Button
        android:id="@+id/btn_2"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:text="按钮2"
        android:textSize="20sp"
        android:textColor="#EE0000"
        android:background="@drawable/bg_btn2"
        android:layout_marginTop="20dp"
        android:layout_below="@id/btn_1"
        android:onClick="ShowToast"/>

    <Button
        android:id="@+id/btn_3"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:text="按钮3"
        android:textSize="20sp"
        android:textColor="#EE0000"
        android:background="@drawable/bg_btn3"
        android:layout_marginTop="20dp"
        android:layout_below="@id/btn_2" />

    <Button
        android:id="@+id/btn_4"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:text="按钮4"
        android:textSize="20sp"
        android:textColor="#FFFFFF"
        android:background="@drawable/bg_btn4"
        android:layout_marginTop="20dp"
        android:layout_below="@id/btn_3"
        android:onClick="ShowToast"/>

    <TextView
        android:id="@+id/tb_1"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:text="按钮5"
        android:textSize="20sp"
        android:background="#1170FF"
        android:layout_below="@id/btn_4"
        android:layout_marginTop="20dp"
        android:gravity="center"/>

</RelativeLayout>

res > drawable > bg_btn2.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">

    <solid
        android:color="#FFA011"/>

    <corners
        android:radius="20dp"/>
</shape>

res > drawable > bg_btn3.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">

    <stroke
        android:width="1dp"
        android:color="#FFA011"/>

    <corners
        android:radius="20dp"/>

</shape>

res > drawable > bg_btn4.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_pressed="true">
        <shape>
            <solid android:color="#FF1111"/>
            <corners android:radius="20dp"/>
        </shape>
    </item>

    <item android:state_pressed="false">
        <shape>
            <solid android:color="#FFA011"/>
            <corners android:radius="20dp"/>
        </shape>
    </item>

</selector>

 

按钮3与其他按钮点击后弹出来的“点击成功”的原理与其他的不同，按钮4点击后会变颜色，按钮5不是用Button写的，是另一种方式。