Android动态设置布局宽高

例如设置一个图片宽高 关键代码：

//取控件当前的布局参数
LinearLayout.LayoutParams params = (LinearLayout.LayoutParams) imageView.getLayoutParams();
//设置宽度值
params.width = dip2px(MainActivity.this, width);
//设置高度值
params.height = dip2px(MainActivity.this, height);
//使设置好的布局参数应用到控件
imageView.setLayoutParams(params);

高度除了可以设置成以上固定的值，也可以设置成wrap_content或match_content

ViewGroup.LayoutParams.WRAP_CONTENT
ViewGroup.LayoutParams.MATCH_PARENT

xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:gravity="center">

    <ImageView
        android:id="@+id/img"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@mipmap/pic1"
        />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:padding="20dp"
        android:orientation="horizontal"
        >

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="设置 （dp）  " />

        <EditText
            android:id="@+id/edit_width"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:hint="宽"
            android:inputType="number"
            />

        <EditText
            android:id="@+id/edit_height"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:hint="高"
            android:inputType="number"
            />

    </LinearLayout>

    <Button
        android:id="@+id/btn_change"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="change"
        />

</LinearLayout>

代码

public class MainActivity extends Activity implements View.OnClickListener {
    private EditText editWidth;
    private EditText editHeight;
    private ImageView imageView;
    private Button button;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        editWidth = findViewById(R.id.edit_width);
        editHeight = findViewById(R.id.edit_height);
        imageView = findViewById(R.id.img);
        button = findViewById(R.id.btn_change);

        button.setOnClickListener(this);
    }

    /**
     * dp转为px
     *
     * @param context  上下文
     * @param dipValue dp值
     * @return
     */
    private int dip2px(Context context, float dipValue) {
        Resources r = context.getResources();
        return (int) TypedValue.applyDimension(
                TypedValue.COMPLEX_UNIT_DIP, dipValue, r.getDisplayMetrics());
    }

    @Override
    public void onClick(View view) {
        if (!TextUtils.isEmpty(editHeight.getText().toString()) && !TextUtils.isEmpty(editWidth.getText().toString())) {
            int width = Integer.parseInt(editWidth.getText().toString());
            int height = Integer.parseInt(editHeight.getText().toString());

            LinearLayout.LayoutParams params = (LinearLayout.LayoutParams) imageView.getLayoutParams();
            params.width = dip2px(MainActivity.this, width);
            params.height = dip2px(MainActivity.this, height);
            // params.setMargins(dip2px(MainActivity.this, 1), 0, 0, 0); // 可以实现设置位置信息，如居左距离，其它类推
            // params.leftMargin = dip2px(MainActivity.this, 1);
            imageView.setLayoutParams(params);
        } else {
            Toast.makeText(MainActivity.this, "请输入宽高！", Toast.LENGTH_LONG).show();
        }
    }
}