Layout的放大和缩小效果例子(ScaleAnimation)

一个Layout从中心放大和缩小的例子,直接上代码: 
1.ScaleDialog.java文件 

package cn.com;

import android.app.Activity;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;

public class ScaleDialog extends Activity implements OnClickListener {

    RelativeLayout layout_parent;

    Button scale_btn;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.first);

        scale_btn = (Button) findViewById(R.id.scale_btn);
        scale_btn.setOnClickListener(this);

        layout_parent = (RelativeLayout) findViewById(R.id.layout_parent);
    }

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        switch (v.getId()) {
        case R.id.scale_btn:
            displayPage();
            v.setEnabled(false);
            break;
        case R.id.dismiss_btn:
            dismissPage();
            break;
        }

    }

    View layout;
    ImageView jobShadow;

    public void displayPage() {
        LayoutInflater inflater = (LayoutInflater) getSystemService(LAYOUT_INFLATER_SERVICE);
        layout = inflater.inflate(R.layout.second, null);
        layout.setId(Constant.KEY_LAYOUT_ID);
        jobShadow = (ImageView) layout.findViewById(R.id.jobShadow);

        Drawable ico = getResources().getDrawable(R.drawable.dbg);
        jobShadow.setBackgroundDrawable(ico);
        ico.mutate().setAlpha(200);

        LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(
                LinearLayout.LayoutParams.FILL_PARENT,
                LinearLayout.LayoutParams.FILL_PARENT);
        layout_parent.addView(layout, layoutParams);

        findDialogView();

        // 显示layout进行缩放动画效果
        ScaleAnimationHelper scaleHelper = new ScaleAnimationHelper(this,
                Constant.KEY_FIRSTPAGE);
        scaleHelper.ScaleOutAnimation(layout);
    }

    public void removeLayout() {

        layout_parent.removeView(layout_parent
                .findViewById(Constant.KEY_LAYOUT_ID));
    }

    Button dismiss_btn;

    public void findDialogView() {
        dismiss_btn = (Button) findViewById(R.id.dismiss_btn);
        dismiss_btn.setOnClickListener(this);
    }

    public void dismissPage() {
        ScaleAnimationHelper scaleHelper = new ScaleAnimationHelper(this,
                Constant.KEY_SECONDPAGE);
        scaleHelper.ScaleInAnimation(layout);
        scale_btn.setEnabled(true);
    }
}

2. ScaleAnimationHelper.java的辅助类 

package cn.com;

import android.content.Context;
import android.view.View;
import android.view.animation.AccelerateInterpolator;
import android.view.animation.Animation;
import android.view.animation.AnimationSet;
import android.view.animation.ScaleAnimation;

public class ScaleAnimationHelper {
    Context con;
    int order;

    public ScaleAnimationHelper(Context con, int order) {
        this.con = con;
        this.order = order;
    }

    DisplayNextView listener;
    ScaleAnimation myAnimation_Scale;
        //放大的类,不需要设置监听器
    public void ScaleOutAnimation(View view) {
        myAnimation_Scale = new ScaleAnimation(0.1f, 1.0f, 0.1f, 1f,
                Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
                0.5f);
        myAnimation_Scale.setInterpolator(new AccelerateInterpolator());
        AnimationSet aa = new AnimationSet(true);
        aa.addAnimation(myAnimation_Scale);
        aa.setDuration(500);

        view.startAnimation(aa);
    }

    public void ScaleInAnimation(View view) {
        listener = new DisplayNextView((ScaleDialog) con, order);
        myAnimation_Scale = new ScaleAnimation(1.0f, 0.0f, 1.0f, 0.0f,
                Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
                0.5f);
        myAnimation_Scale.setInterpolator(new AccelerateInterpolator());
               //缩小Layout的类,在动画结束需要从父View移除它
        myAnimation_Scale.setAnimationListener(listener);
        AnimationSet aa = new AnimationSet(true);
        aa.addAnimation(myAnimation_Scale);
        aa.setDuration(500);

        view.startAnimation(aa);
    }
}

3. DisplayNextView.java动画结束的监听类 

package cn.com;

import android.app.Activity;
import android.view.animation.Animation;

public class DisplayNextView implements Animation.AnimationListener {

    Object obj;

    // 动画监听器的构造函数
    Activity ac;
    int order;

    public DisplayNextView(Activity ac, int order) {
        this.ac = ac;
        this.order = order;
    }

    public void onAnimationStart(Animation animation) {
    }

    public void onAnimationEnd(Animation animation) {
        doSomethingOnEnd(order);
    }

    public void onAnimationRepeat(Animation animation) {
    }

    private final class SwapViews implements Runnable {
        public void run() {
            switch (order) {
            case Constant.KEY_SECONDPAGE:
                ((ScaleDialog) ac).removeLayout();
                break;
            }
        }
    }

    public void doSomethingOnEnd(int _order) {
        switch (_order) {

        case Constant.KEY_SECONDPAGE:
            ((ScaleDialog) ac).layout_parent.post(new SwapViews());
            break;
        }
    }
}

4. Constant.java标识ID常量的类 

package cn.com;

public class Constant {

    public final static int KEY_FIRSTPAGE = 1;

    public final static int KEY_SECONDPAGE = 2;

    public final static int KEY_LAYOUT_ID = 3;
}

5.first.xml文件 

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="fill_parent"
    android:layout_height="fill_parent" android:id="@+id/layout_parent">
    <Button android:text="Scale" android:id="@+id/scale_btn"
        android:layout_width="fill_parent" android:layout_height="wrap_content"></Button>
</RelativeLayout>

6.second.xml文件 

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent" android:layout_height="fill_parent"
    android:id="@+id/jobContent">
    <ImageView android:layout_width="fill_parent"
        android:layout_height="fill_parent" android:id="@+id/jobShadow" />
    <Button android:layout_width="fill_parent" android:text="Dismiss"
        android:layout_marginTop="20dp" android:layout_height="wrap_content"
        android:src="@drawable/jobbg" android:layout_alignParentBottom="true"
        android:id="@+id/dismiss_btn" />
</RelativeLayout>