自定义开关

最新推荐文章于 2024-10-18 16:49:17 发布

原创最新推荐文章于 2024-10-18 16:49:17 发布 · 402 阅读

0 ·

CC 4.0 BY-SA版权

android 专栏收录该内容

38 篇文章

订阅专栏

本文介绍了一种自定义Android开关控件的方法，包括View的绘制、缩放、状态切换等核心功能，并演示了如何在Activity中引用及监听开关状态的变化。

1、自定义view，背景和开关的绘制

package view;
import com.example.selftoggle.R;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.view.View;

public class SwichToggle extends View {
private Paint mPaint;
private boolean mIstoggleon = false;
private float mScaleNum = 0.5f;

private Bitmap mNewBack_bt;
private Bitmap mNewSwitchto;

//构造方法
public SwichToggle(Context context, AttributeSet attrs) {
super(context, attrs);

//初始化drawable图片
Bitmap mBack_bt = BitmapFactory.decodeResource(getResources(), R.drawable.switch_background);
Bitmap mSwithcto = BitmapFactory.decodeResource(getResources(), R.drawable.switch_button);
mPaint = new Paint();

mNewBack_bt = scaleBitmap(mBack_bt, mScaleNum);
mNewSwitchto = scaleBitmap(mSwithcto, mScaleNum);
setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {

mIstoggleon=!mIstoggleon;
invalidate();
if (mListener != null) {
mListener.setIstoggleOnOrNot(mIstoggleon);
}

}
});

}

//重写测量的方法
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
// 根据图片的高度来设置高度和宽度
setMeasuredDimension(mNewBack_bt.getWidth(), mNewBack_bt.getHeight());

}

@Override
protected void onDraw(Canvas canvas) {
// 画背景
canvas.drawBitmap(mNewBack_bt, 0, 0, mPaint);

//画开关
if (mIstoggleon) {
canvas.drawBitmap(mNewSwitchto, mNewBack_bt.getWidth()-mNewSwitchto.getWidth(), 0, mPaint);
}else {
canvas.drawBitmap(mNewSwitchto, 0, 0, mPaint);
}

}

// 接口回调来传递开关的状态

private setIstoggleOnLister mListener;
public interface setIstoggleOnLister{
void setIstoggleOnOrNot(boolean istoggleon);
}

public void setIstoggleOnLister(setIstoggleOnLister listener){
mListener = listener;
}

//缩放bitmap的方法
private Bitmap scaleBitmap(Bitmap bitmap,float scaleNum) {
Matrix matrix = new Matrix();
matrix.postScale(scaleNum,scaleNum);
Bitmap resizeBmp = Bitmap.createBitmap(bitmap,0,0,bitmap.getWidth(),bitmap.getHeight(),matrix,true);
return resizeBmp;
}
}

2、布局的引用：

<view.SwichToggle
android:id="@+id/iv_toggle"
android:layout_width="20dp"
android:layout_height="20dp"
/>

3、activity中的引用：

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mIs_toggle = (SwichToggle) findViewById(R.id.iv_toggle);

initListener();
}

private void initListener() {
// TODO Auto-generated method stub
mIs_toggle.setIstoggleOnLister(new setIstoggleOnLister() {
@Override
public void setIstoggleOnOrNot(boolean istoggleon) {
if (istoggleon) {
Toast.makeText(MainActivity.this, "关闭了", 1).show();
}else {
Toast.makeText(MainActivity.this, “打开了”，1).show();

}
}
});
}