为水平和垂直居中的ImageView设置动画

时间:2014-05-09 12:29:46

标签: android android-animation

我有一个水平和垂直居中的ImageView,我需要使用此ImageView向上移动来创建动画。

我该怎么做?

我有以下代码:

XML     

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/image_logo_splash"
        android:src="@drawable/logo"
        android:layout_marginTop="140dp"
        android:layout_centerHorizontal="true" />

</RelativeLayout>

爪哇

        Animation logoAnimation = new Animation() {
        @Override
        protected void applyTransformation(float interpolatedTime, Transformation t) {
            final ImageView logoImage = (ImageView)findViewById(R.id.image_logo_splash);
            final float newTopMargin = 20;

            RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.MATCH_PARENT, RelativeLayout.LayoutParams.MATCH_PARENT);
            params.topMargin = (int)(newTopMargin * interpolatedTime);
            logoImage.setLayoutParams(params);
        }
    };

    ImageView logoImage = (ImageView)findViewById(R.id.image_logo_splash);
    logoImage.startAnimation(logoAnimation);

1 个答案:

答案 0 :(得分:3)

第1页facebook图像上升所以你必须将它从当前位置翻译到顶部

<translate
    android:fromYDelta="0%p"
    android:toYDelta="-30%p"
    android:duration="1000" />

这里android:fromYDelta是起始位置,android:toYDelta是百分比的结束位置,即-30%和android:持续时间是及时,即1秒

第二个现在附上一个监听器来检查动画何时完成。立即淡入你的登录框

这是代码

MinActivity.java

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.Animation;
import android.view.animation.Animation.AnimationListener;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button startAnimation =(Button) findViewById(R.id.button1);
        final LinearLayout LoginBox = (LinearLayout) findViewById(R.id.LoginBox);
        LoginBox.setVisibility(View.GONE);
        startAnimation.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
                Animation animTranslate  = AnimationUtils.loadAnimation(MainActivity.this, R.anim.translate);
                animTranslate.setAnimationListener(new AnimationListener() {

                    @Override
                    public void onAnimationStart(Animation arg0) { }

                    @Override
                    public void onAnimationRepeat(Animation arg0) { }

                    @Override
                    public void onAnimationEnd(Animation arg0) {
                        LoginBox.setVisibility(View.VISIBLE);
                        Animation animFade  = AnimationUtils.loadAnimation(MainActivity.this, R.anim.fade);
                        LoginBox.startAnimation(animFade);
                    }
                });
                ImageView imgLogo = (ImageView) findViewById(R.id.imageView1);
                imgLogo.startAnimation(animTranslate);

            }
        });

    }

}

在anim文件夹中使用这些xml的

fade.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
    android:fillAfter="true"
    android:interpolator="@android:anim/accelerate_decelerate_interpolator" >
    <alpha
        android:duration="200"
        android:fromAlpha="0.0"
        android:interpolator="@android:anim/accelerate_interpolator"
        android:toAlpha="1.0" />

</set>

translate.xml

<?xml version="1.0" encoding="utf-8"?>
<set
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:interpolator="@android:anim/accelerate_decelerate_interpolator"
    android:fillAfter="true">

   <translate
        android:fromYDelta="0%p"
        android:toYDelta="-30%p"
        android:duration="1000" />
</set>

布局activity_main.xml

<RelativeLayout 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:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:text="Start Animation" />

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:src="@drawable/ic_launcher" />

    <LinearLayout
        android:id="@+id/LoginBox"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:orientation="vertical" >