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[Android]Java中点击事件的四种写法

pinnsvin 2017-05-17 18:39 原文

点击事件的必备条件：实现OnClickListener接口，重写onclick(View v)方法

以拨号简单案例为例，如下图效果：
演示图片

逻辑流程：

  1. 获取点击对象，获取数据
  2. 给对象设置监听类
  3. 实现OnClickListener接口,重写onClick(View v)方法

onClick(View v)逻辑：

  1. 获取输入内容：使用EditText对象的getText()方法，该方法返回值为Editable，需要用toString()转换成String类型

  2. 判断输入是否为空，TextUtils.isEmpty(str)方法判断字符串str是否为空

  3. 为空则提示号码不能为空，使用Toast.makeText(MainActivity.this, "号码不能为空", Toast.LENGTH_SHORT).show();,
    Toast makeText (Context context, CharSequence text, int duration)返回值为Toast，参数列表（Context对象，提示内容，显示时长）

  1. 如果不为空，new 一个Intent对象，使用Intent对象的setAction(String action)方法设置动作，使用Intent对象的setData(Uri uriData)方法设置数据。startActivity(Intent intent)方法启动Activity。

注：应该在程序清单文件AndroidManifest.xml中添加<uses-permission android:name="android.permission.CALL_PHONE"/>，拨打电话时，美国紧急电话不会直接拨打

三种方法：第四种不推荐，前三种酌情使用

1. 内部实现类

布局文件：activity_main.xml

    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="${relativePackage}.${activityClass}" >


    <EditText
        android:id="@+id/editText1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:focusable="true"
        android:focusableInTouchMode="true"
        android:hint="在此输入电话号码">

    </EditText>

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/editText1"
        android:layout_marginTop="14dp"
        android:text="拨打此号码" />

    <Button
        android:id="@+id/button2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_below="@+id/button1"
        android:text="Button2" />

    <Button
        android:id="@+id/button3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_below="@+id/button2"
        android:text="Button3" />


</RelativeLayout>

MainActivity.java

    package com.example.onclick1;

    import android.app.Activity;
    import android.content.Intent;
    import android.net.Uri;
    import android.os.Bundle;
    import android.os.storage.OnObbStateChangeListener;
    import android.text.TextUtils;
    import android.view.Menu;
    import android.view.MenuItem;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.Button;
    import android.widget.EditText;
    import android.widget.Toast;

    public class MainActivity extends Activity {

    	private EditText editText;
    	@Override
    	protected void onCreate(Bundle savedInstanceState) {
    		super.onCreate(savedInstanceState);
    		setContentView(R.layout.activity_main);
    		editText = (EditText) findViewById(R.id.editText1);
    		Button button1 = (Button) findViewById(R.id.button1);
    		Button button2 = (Button) findViewById(R.id.button2);
    		Button button3 = (Button) findViewById(R.id.button3);

    		//设置监听类
    		button1.setOnClickListener(new MyOnClickListener());
    		button2.setOnClickListener(new MyOnClickListener());
    		button3.setOnClickListener(new MyOnClickListener());
    	}
    	private class MyOnClickListener implements OnClickListener{

    		@Override
    		public void onClick(View v) {
    			int i = v.getId();
    			switch (i) {
    			case R.id.button1:
    				String number = editText.getText().toString();
    				if (TextUtils.isEmpty(number)) {
    					Toast.makeText(MainActivity.this, "号码不能为空", Toast.LENGTH_SHORT).show();
    				}else {
    					Intent intent = new Intent();
    					intent.setAction(intent.ACTION_CALL);
    					Uri data = Uri.parse("tel:"+number);
    					intent.setData(data);
    					startActivity(intent);
    				}

    				break;
    			case R.id.button2:
    				Toast.makeText(MainActivity.this, "你点击了Button2", Toast.LENGTH_SHORT).show();
    				break;
    			case R.id.button3:
    				Toast.makeText(MainActivity.this, "你点击了Button3", Toast.LENGTH_SHORT).show();
    				break;
    			}
    		}

    	}
    }

2. 内部匿名类

MainActivity.java

	package com.example.onclick1;

    import android.app.Activity;
    import android.content.Intent;
    import android.net.Uri;
    import android.os.Bundle;
    import android.os.storage.OnObbStateChangeListener;
    import android.text.TextUtils;
    import android.view.Menu;
    import android.view.MenuItem;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.Button;
    import android.widget.EditText;
    import android.widget.Toast;

    public class MainActivity extends Activity {

    	private EditText editText;
    	@Override
    	protected void onCreate(Bundle savedInstanceState) {
    		super.onCreate(savedInstanceState);
    		setContentView(R.layout.activity_main);
    		editText = (EditText) findViewById(R.id.editText1);
    		Button button1 = (Button) findViewById(R.id.button1);
    		Button button2 = (Button) findViewById(R.id.button2);
    		Button button3 = (Button) findViewById(R.id.button3);

    		//设置监听类
    		button1.setOnClickListener(new OnClickListener() {

    			@Override
    			public void onClick(View v) {
    				String number = editText.getText().toString();
    				if(TextUtils.isEmpty(number)){
    					Toast.makeText(MainActivity.this, "[内部匿名类]号码不能为空", Toast.LENGTH_SHORT).show();
    				}else{
    					Intent intent = new Intent();
    					intent.setAction(intent.ACTION_CALL);
    					intent.setData(Uri.parse("tel:"+number));
    					startActivity(intent);
    				}
    			}
    		});
    		button2.setOnClickListener(new OnClickListener() {

    			@Override
    			public void onClick(View v) {
    				Toast.makeText(MainActivity.this, "[内部匿名类]你点击了Button2", Toast.LENGTH_SHORT).show();
    			}
    		});
    		button3.setOnClickListener(new OnClickListener() {

    			@Override
    			public void onClick(View v) {
    				Toast.makeText(MainActivity.this, "[内部匿名类]你又点击了button3", Toast.LENGTH_SHORT).show();

    			}
    		});
    	}
    }

3. Activity实现OnClickLitener

MainActivity.java

    package com.example.onclick1;

    import android.app.Activity;
    import android.content.Intent;
    import android.net.Uri;
    import android.os.Bundle;
    import android.os.storage.OnObbStateChangeListener;
    import android.text.TextUtils;
    import android.view.Menu;
    import android.view.MenuItem;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.Button;
    import android.widget.EditText;
    import android.widget.Toast;

    public class MainActivity extends Activity implements OnClickListener{

    	private EditText editText;
    	@Override
    	protected void onCreate(Bundle savedInstanceState) {
    		super.onCreate(savedInstanceState);
    		setContentView(R.layout.activity_main);
    		editText = (EditText) findViewById(R.id.editText1);
    		Button button1 = (Button) findViewById(R.id.button1);
    		Button button2 = (Button) findViewById(R.id.button2);
    		Button button3 = (Button) findViewById(R.id.button3);

    		//设置监听类
    		button1.setOnClickListener(this);
    		button2.setOnClickListener(this);
    		button3.setOnClickListener(this);
    	}
    	@Override
    	public void onClick(View v) {
    		int id = v.getId();
    		switch (id) {
    		case R.id.button1:
    			String number = editText.getText().toString();
    			if (TextUtils.isEmpty(number)) {
    				Toast.makeText(this, "[Activity实现类]号码不能为空", Toast.LENGTH_SHORT).show();
    			}else {
    				Intent intent = new Intent();
    				intent.setAction(intent.ACTION_CALL);
    				intent.setData(Uri.parse("tel:"+number));
    				startActivity(intent);
    			}
    			break;
    		case R.id.button2:
    			Toast.makeText(this, "[Activity实现类]你点击了Button2", Toast.LENGTH_SHORT).show();
    			break;
    		case R.id.button3:
    			Toast.makeText(this, "[Activity实现类]你点击了Button3", Toast.LENGTH_SHORT).show();
    			break;
    		}
    	}
    }

4. 结合layout文件声明方法

activity_main.xml

    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:context="${relativePackage}.${activityClass}" >


        <EditText
            android:id="@+id/editText1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:focusable="true"
            android:focusableInTouchMode="true"
            android:hint="在此输入电话号码">

        </EditText>

        <Button
            android:id="@+id/button1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@+id/editText1"
            android:layout_marginTop="14dp"
            android:onClick="button"
            android:text="拨打此号码" />

        <Button
            android:id="@+id/button2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentLeft="true"
            android:layout_below="@+id/button1"
            android:onClick="button"
            android:text="Button2" />

        <Button
            android:id="@+id/button3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentLeft="true"
            android:layout_below="@+id/button2"
            android:onClick="button"
            android:text="Button3" />


    </RelativeLayout>

MainActivity.java

    package com.example.onclick1;

    import android.app.Activity;
    import android.content.Intent;
    import android.net.Uri;
    import android.os.Bundle;
    import android.os.storage.OnObbStateChangeListener;
    import android.text.TextUtils;
    import android.view.Menu;
    import android.view.MenuItem;
    import android.view.View;
    import android.widget.EditText;
    import android.widget.Toast;

    public class MainActivity extends Activity{

    	@Override
    	protected void onCreate(Bundle savedInstanceState) {
    		super.onCreate(savedInstanceState);
    		setContentView(R.layout.activity_main);
    	}
    	public void button(View v) {
    	EditText editText = (EditText) findViewById(R.id.editText1);
    		switch (v.getId()) {
    		case R.id.button1:
    			String number = editText.getText().toString();
    			if (TextUtils.isEmpty(number)) {
    				Toast.makeText(this, "[布局文件中Button的android:onClick属性]号码不能为空", Toast.LENGTH_SHORT).show();
    			}else {
    				Intent intent = new Intent();
    				intent.setAction(intent.ACTION_CALL);
    				intent.setData(Uri.parse("tel:"+number));
    				startActivity(intent);
    			}
    			break;
    		case R.id.button2:
    			Toast.makeText(this, "[布局文件中Button的android:onClick属性]你点击了Button2", Toast.LENGTH_SHORT).show();
    			break;
    		case R.id.button3:
    			Toast.makeText(this, "[布局文件中Button的android:onClick属性]你点击了Button3", Toast.LENGTH_SHORT).show();
    			break;
    		}
    	}
    }

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