java - 我的 ImageView 的动画高度

Question

我正在尝试使用稍后从数据库收到的 var 来为 ImageView 的高度设置动画。检查了堆栈和其他网站，但没有找到合适的答案，不想使用 xml 来做。这是我已经拥有的一些代码:

    <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"
    tools:context=".MainActivity" >

    <ImageView
        android:id="@+id/background"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/enkelzijdig" />

    <ImageView
        android:id="@+id/bar1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="75dp"
        android:layout_marginTop="150dp"
        android:src="@drawable/animatiebalk" />


    </RelativeLayout>





**than where the magic should happen:**





    package com.example.grafiek;



    import android.app.Activity;
    import android.os.Bundle;
    import android.view.Window;
    import android.widget.ImageView;


    public class MainActivity extends Activity{

    ImageView balk1;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.activity_main);

        balk1 = (ImageView)findViewById(R.id.balk1);

    }


    public void ScaleAnimation (float fromX, float toX, float fromY, float toY){

                no clue what to do


    }

     }

Answer 1

使用动画来做到这一点——

Animation fadeInFromTopAnimation = AnimationUtils
                            .loadAnimation(ActivityName.this, R.anim.slide_up);
                    fadeInFromTopAnimation
                            .setAnimationListener(new AnimationListener() {
                                public void onAnimationStart(Animation anim) {

                                }

                                public void onAnimationEnd(Animation anim) {
                                    imageView.setVisibility(View.GONE);
                                }

                                public void onAnimationRepeat(Animation anim) {
                                }
                            });


                    imageView.startAnimation(fadeInFromTopAnimation);

你必须在anim文件夹中制作以下slide_up.xml---

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

<alpha
    android:fromAlpha       = "1"
    android:toAlpha         = "0"
    android:duration        = "100">
</alpha>

<scale
    android:fromXScale      = "1"
    android:fromYScale      = "1"
    android:toXScale        = "1"
    android:toYScale        = "0"
    android:pivotX          = "50%"
    android:pivotY          = "0%"
    android:duration        = "100">
</scale>
</set>