Android的ImageView的放大和缩小功能 [英] Android imageView Zoom-in and Zoom-Out

问题描述

我是新来的Andr​​oid应用程序，我想放大和缩小功能ImageView.I试图大多数样品，但在ImageView的所有图像得到放大和缩小，out.I要放大-in和缩小ImageView.I想增加ImageView的宽度和高度，同时放大和缩小ImageView的宽度和高度，而变焦out.Can任何一个建议我？

Hi i am new to Android application i want to Zoom-in and Zoom-out ImageView.I tried most of the sample but in all that image in the imageview is get Zoom-in and Zoom-out.I want to Zoom-in and Zoom-out ImageView.I want to increase imageview width and height while Zoom-in and reduce imageview width and height while Zoom-out.Can any one suggest me?

推荐答案

请两个Java类

变焦类

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.drawable.Drawable;
import android.view.KeyEvent;
import android.view.View;
import android.widget.Button;
import android.widget.ImageButton;

public class Zoom extends View {

    private Drawable image;
    ImageButton img,img1;
    private int zoomControler=20;

    public Zoom(Context context){
            super(context);

            image=context.getResources().getDrawable(R.drawable.j);
            //image=context.getResources().getDrawable(R.drawable.icon);

            setFocusable(true);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        //here u can control the width and height of the images........ this line is very important
        image.setBounds((getWidth()/2)-zoomControler, (getHeight()/2)-zoomControler, (getWidth()/2)+zoomControler, (getHeight()/2)+zoomControler);
        image.draw(canvas);
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {

            if(keyCode==KeyEvent.KEYCODE_DPAD_UP){
                    // zoom in
                    zoomControler+=10;
            }
            if(keyCode==KeyEvent.KEYCODE_DPAD_DOWN){
                    // zoom out
                    zoomControler-=10;
            }
            if(zoomControler<10){
                    zoomControler=10;
            }

            invalidate();
            return true;
    }
}

请二等

import android.app.Activity;
import android.os.Bundle;

public class Zoomexample extends Activity {
   /** Called when the activity is first created. */

   @Override
   public void onCreate(Bundle icicle) {
       super.onCreate(icicle);
       setContentView(new Zoom(this));
   }
}

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