1.自定义属性values/attrs.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<declare-styleable name="ToggleView">
<attr name="switch_background" format="reference" />
<attr name="slide_button" format="reference" />
<attr name="switch_state" format="boolean" />
</declare-styleable>
</resources>2.view的java文件：
package zdl.switchbutton.view;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
/**
* 自定义开关
*
*/
public class ToggleView extends View {
private Bitmap switchBackgroupBitmap; // 背景图片
private Bitmap slideButtonBitmap; // 滑块图片
private Paint paint; // 画笔
private boolean mSwitchState = false; // 开关状态, 默认false
private float currentX;
/**
* 用于代码创建控件
*
* @param context
*/
public ToggleView(Context context) {
super(context);
init();
}
/**
* 用于在xml里使用, 可指定自定义属性
*
* @param context
* @param attrs
*/
public ToggleView(Context context, AttributeSet attrs) {
super(context, attrs);
init();
// 获取配置的自定义属性
String namespace = "http://toly.android.com/apk/res/zdl.switchbutton.view.ToggleView";
int switchBackgroundResource = attrs.getAttributeResourceValue(namespace, "switch_background", -1);
int slideButtonResource = attrs.getAttributeResourceValue(namespace, "slide_button", -1);
mSwitchState = attrs.getAttributeBooleanValue(namespace, "switch_state", false);
setSwitchBackgroundResource(switchBackgroundResource);
setSlideButtonResource(slideButtonResource);
}
/**
* 用于在xml里使用, 可指定自定义属性, 如果指定了样式, 则走此构造函数
*F:\Android\SwitchButton\app\src\main\java\zdl\switchbutton\view\ToggleView.java
* zdl.switchbutton.view.ToggleView
* @param context
* @param attrs
* @param defStyle
*/
public ToggleView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
private void init() {
paint = new Paint();
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
setMeasuredDimension(switchBackgroupBitmap.getWidth(), switchBackgroupBitmap.getHeight());
}
// Canvas 画布, 画板. 在上边绘制的内容都会显示到界面上.
@Override
protected void onDraw(Canvas canvas) {
// 1. 绘制背景
canvas.drawBitmap(switchBackgroupBitmap, 0, 0, paint);
// 2. 绘制滑块
if (isTouchMode) {
// 根据当前用户触摸到的位置画滑块
// 让滑块向左移动自身一半大小的位置
float newLeft = currentX - slideButtonBitmap.getWidth() / 2.0f;
int maxLeft = switchBackgroupBitmap.getWidth() - slideButtonBitmap.getWidth();
// 限定滑块范围
if (newLeft < 0) {
newLeft = 0; // 左边范围
} else if (newLeft > maxLeft) {
newLeft = maxLeft; // 右边范围
}
canvas.drawBitmap(slideButtonBitmap, newLeft, 0, paint);
} else {
// 根据开关状态boolean, 直接设置图片位置
if (mSwitchState) {// 开
int newLeft = switchBackgroupBitmap.getWidth() - slideButtonBitmap.getWidth();
canvas.drawBitmap(slideButtonBitmap, newLeft, 0, paint);
} else {// 关
canvas.drawBitmap(slideButtonBitmap, 0, 0, paint);
}
}
}
boolean isTouchMode = false;
private OnSwitchListener onSwitchListener;
// 重写触摸事件, 响应用户的触摸.
@Override
public boolean onTouchEvent(MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
isTouchMode = true;
System.out.println("event: ACTION_DOWN: " + event.getX());
currentX = event.getX();
break;
case MotionEvent.ACTION_MOVE:
System.out.println("event: ACTION_MOVE: " + event.getX());
currentX = event.getX();
break;
case MotionEvent.ACTION_UP:
isTouchMode = false;
System.out.println("event: ACTION_UP: " + event.getX());
currentX = event.getX();
float center = switchBackgroupBitmap.getWidth() / 2.0f;
// 根据当前按下的位置, 和控件中心的位置进行比较.
boolean state = currentX > center;
// 如果开关状态变化了, 通知界面. 里边开关状态更新了.
if (state != mSwitchState && onSwitchListener != null) {
// 把最新的boolean, 状态传出去了
onSwitchListener.onStateUpdate(state);
}
mSwitchState = state;
break;
default:
break;
}
// 重绘界面
invalidate(); // 会引发onDraw()被调用, 里边的变量会重新生效.界面会更新
return true; // 消费了用户的触摸事件, 才可以收到其他的事件.
}
/**
* 设置背景图
*
* @param switchBackground
*/
public void setSwitchBackgroundResource(int switchBackground) {
switchBackgroupBitmap = BitmapFactory.decodeResource(getResources(), switchBackground);
}
/**
* 设置滑块图片资源
*
* @param slideButton
*/
public void setSlideButtonResource(int slideButton) {
slideButtonBitmap = BitmapFactory.decodeResource(getResources(), slideButton);
}
/**
* 设置开关状态
*/
public void setSwitchState(boolean mSwitchState) {
this.mSwitchState = mSwitchState;
}
public interface OnSwitchListener {
// 状态回调, 把当前状态传出去
void onStateUpdate(boolean state);
}
public void setOnSwitchListener(OnSwitchListener onSwitchListener) {
this.onSwitchListener = onSwitchListener;
}
}
3.layout中使用
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:toly="http://toly.android.com/apk/res/zdl.switchbutton.view.ToggleView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<zdl.switchbutton.view.ToggleView
android:id="@+id/toggleView"
toly:switch_background="@drawable/switch_background"
toly:slide_button="@drawable/slide_button"
toly:switch_state="false"
android:layout_width="20dp"
android:layout_height="wrap_content"/>
</LinearLayout>4.MainActivity.java中：
package zdl.switchbutton;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;
import zdl.switchbutton.view.ToggleView;
public class MainActivity extends AppCompatActivity {
private Toolbar mTb;
private ToggleView toggleView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
toggleView = (ToggleView) findViewById(R.id.toggleView);
// 设置开关更新监听
toggleView.setOnSwitchListener(new ToggleView.OnSwitchListener(){
@Override
public void onStateUpdate(boolean state) {
Toast.makeText(getApplicationContext(), "state: " + state, 0).show();
}
});
}
