android中动态修改ImageView控件的宽高度

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity"> <LinearLayout
android:layout_width="match_parent"
android:layout_height="60dp"
android:gravity="center"
android:orientation="horizontal"> <Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="放大" />
<Button
android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="缩小" />
</LinearLayout> <ImageView
android:id="@+id/imageView"
android:layout_width="150dp"
android:layout_height="150dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:srcCompat="@drawable/img01" /></android.support.constraint.ConstraintLayout>

package com.example.chenrui.app1;import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ImageView;public class MainActivity extends AppCompatActivity { @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main); final ImageView image = findViewById(R.id.imageView);
Button button1 = findViewById(R.id.button1);
button1.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v) {
ViewGroup.LayoutParams params = image.getLayoutParams();
params.width = params.width + 50;
params.height = params.height + 50;
image.setLayoutParams(params);
}
}); Button button2 = findViewById(R.id.button2);
button2.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v) {
ViewGroup.LayoutParams params = image.getLayoutParams();
params.width = params.width - 50;
params.height = params.height - 50;
image.setLayoutParams(params);
}
});
}
}