Button的简要说明

根据你是否想要一个带有文本的按钮，一个图标，或者两者，你可以在三种方式中创建按钮来进行布局：

With text, using the Button class:

<Buttonandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:text="@string/button_text"... />

With an icon, using the ImageButton class:

<ImageButtonandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:src="@drawable/button_icon"... />

With text and an icon, using the Button class with the android:drawableLeft attribute:

<Buttonandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:text="@string/button_text"android:drawableLeft="@drawable/button_icon"... />

按钮的响应

1) 在xml中定义的Button中增加属性android:onClick

在xml中定义android:onClick属性：

<?xml version="1.0" encoding="utf-8"?>
<Button xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="@string/button_send"android:onClick="sendMessage" />

在MainActivity中定义sendMessage方法：

public void sendMessage(View view) {// Do something in response to button click
}

2) 在代码中使用OnClickListener

Button button = (Button) findViewById(R.id.button_send);
button.setOnClickListener(new View.OnClickListener() {public void onClick(View v) {// Do something in response to button click
    }
});

按钮样式

1) Borderless button : To create a borderless button, apply the borderlessButtonStyle style to the button.

<Buttonandroid:onClick="sendMessage"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="bordless button"style="?android:attr/borderlessButtonStyle" />

2) Custom background: Instead of supplying a simple bitmap or color, however, your background should be a state list resource that changes appearance depending on the button's current state

Create three bitmaps for the button background that represent the default, pressed, and focused button states.
Place the bitmaps into the res/drawable/ directory of your project. Be sure each bitmap is named properly to reflect the button state that they each represent.

Create a new XML file in the res/drawable/ directory (name it something like button_custom.xml). Insert the following XML

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android"><item android:drawable="@drawable/button_pressed"android:state_pressed="true" /><item android:drawable="@drawable/button_focused"android:state_focused="true" /><item android:drawable="@drawable/button_default" />
</selector>

Then simply apply the drawable XML file as the button background

<Buttonandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:text="send button"android:background="@drawable/button_custom"  />

测试的项目

项目结构：

MainActivity.java:

package com.huhx.linux.buttontest;import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;public class MainActivity extends AppCompatActivity {private Button button;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);button = (Button) findViewById(R.id.sendButton);button.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {Toast.makeText(MainActivity.this, "button click", Toast.LENGTH_SHORT).show();}});}// bordless buttonpublic void sendMessage(View view) {Toast.makeText(MainActivity.this, "Borderless Button", Toast.LENGTH_SHORT).show();}
}

button_custom.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android"><item android:drawable="@drawable/button_pressed"android:state_pressed="true" /><item android:drawable="@drawable/button_focused"android:state_focused="true" /><item android:drawable="@drawable/button_default" />
</selector>

activity_main.xml.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"android:orientation="vertical"tools:context="com.huhx.linux.buttontest.MainActivity"><Buttonandroid:id="@+id/sendButton"android:text="text button"android:layout_width="wrap_content"android:layout_height="wrap_content" /><ImageButtonandroid:src="@mipmap/ic_launcher"android:layout_width="wrap_content"android:layout_height="wrap_content" /><Buttonandroid:drawableRight="@mipmap/ic_launcher"android:text="Linux"android:layout_width="wrap_content"android:layout_height="wrap_content" /><Buttonandroid:onClick="sendMessage"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="bordless button"style="?android:attr/borderlessButtonStyle" /><Buttonandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:text="send button"android:background="@drawable/button_custom"  />
</LinearLayout>