我创建了一些自定义元素,并希望以编程方式将它们放置在右上角(距离上边缘n个像素,距离右边缘m个像素)。因此,我需要获得屏幕宽度和屏幕高度,然后设置位置:

int px = screenWidth - m;
int py = screenHeight - n;

如何在主活动中获取screenWidth和screenHeight?


当前回答

public class AndroidScreenActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        DisplayMetrics dm = new DisplayMetrics();
        getWindowManager().getDefaultDisplay().getMetrics(dm);
        String str_ScreenSize = "The Android Screen is: "
                                   + dm.widthPixels
                                   + " x "
                                   + dm.heightPixels;

        TextView mScreenSize = (TextView) findViewById(R.id.strScreenSize);
        mScreenSize.setText(str_ScreenSize);
    }
}

其他回答

在活动的onCreate中,有时需要知道布局可用空间的精确尺寸。经过一番思考,我想出了这种方法。

public class MainActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        startActivityForResult(new Intent(this, Measure.class), 1);
        // Return without setting the layout, that will be done in onActivityResult.
    }

    @Override
    protected void onActivityResult (int requestCode, int resultCode, Intent data) {
        // Probably can never happen, but just in case.
        if (resultCode == RESULT_CANCELED) {
            finish();
            return;
        }
        int width = data.getIntExtra("Width", -1);
        // Width is now set to the precise available width, and a layout can now be created.            ...
    }
}

public final class Measure extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
       // Create a LinearLayout with a MeasureFrameLayout in it.
        // Just putting a subclass of LinearLayout in works fine, but to future proof things, I do it this way.
        LinearLayout linearLayout = new LinearLayout(this);
        LinearLayout.LayoutParams matchParent = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT);
        MeasureFrameLayout measureFrameLayout = new MeasureFrameLayout(this);
        measureFrameLayout.setLayoutParams(matchParent);
        linearLayout.addView(measureFrameLayout);
        this.addContentView(linearLayout, matchParent);
        // measureFrameLayout will now request this second activity to finish, sending back the width.
    }

    class MeasureFrameLayout extends FrameLayout {
        boolean finished = false;
        public MeasureFrameLayout(Context context) {
            super(context);
        }

        @SuppressLint("DrawAllocation")
        @Override
        protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
            super.onMeasure(widthMeasureSpec, heightMeasureSpec);
            if (finished) {
                return;
            }
            finished = true;
            // Send the width back as the result.
            Intent data = new Intent().putExtra("Width", MeasureSpec.getSize(widthMeasureSpec));
            Measure.this.setResult(Activity.RESULT_OK, data);
            // Tell this activity to finish, so the result is passed back.
            Measure.this.finish();
        }
    }
}

如果出于某种原因,您不想将另一个活动添加到Android清单中,可以这样做:

public class MainActivity extends Activity {
    static Activity measuringActivity;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        Bundle extras = getIntent().getExtras();
        if (extras == null) {
            extras = new Bundle();
        }
        int width = extras.getInt("Width", -2);
        if (width == -2) {
            // First time in, just start another copy of this activity.
            extras.putInt("Width", -1);
            startActivityForResult(new Intent(this, MainActivity.class).putExtras(extras), 1);
            // Return without setting the layout, that will be done in onActivityResult.
            return;
        }
        if (width == -1) {
            // Second time in, here is where the measurement takes place.
            // Create a LinearLayout with a MeasureFrameLayout in it.
            // Just putting a subclass of LinearLayout in works fine, but to future proof things, I do it this way.
            LinearLayout linearLayout = new LinearLayout(measuringActivity = this);
            LinearLayout.LayoutParams matchParent = new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
            MeasureFrameLayout measureFrameLayout = new MeasureFrameLayout(this);
            measureFrameLayout.setLayoutParams(matchParent);
            linearLayout.addView(measureFrameLayout);
            this.addContentView(linearLayout, matchParent);
            // measureFrameLayout will now request this second activity to finish, sending back the width.
        }
    }

    @Override
    protected void onActivityResult (int requestCode, int resultCode, Intent data) {
        // Probably can never happen, but just in case.
        if (resultCode == RESULT_CANCELED) {
            finish();
            return;
        }
        int width = data.getIntExtra("Width", -3);
        // Width is now set to the precise available width, and a layout can now be created. 
        ...
    }

class MeasureFrameLayout extends FrameLayout {
    boolean finished = false;
    public MeasureFrameLayout(Context context) {
        super(context);
    }

    @SuppressLint("DrawAllocation")
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        if (finished) {
            return;
        }
        finished = true;
        // Send the width back as the result.
        Intent data = new Intent().putExtra("Width", MeasureSpec.getSize(widthMeasureSpec));
        MainActivity.measuringActivity.setResult(Activity.RESULT_OK, data);
        // Tell the (second) activity to finish.
        MainActivity.measuringActivity.finish();
    }
}    

对于使用XML进行动态缩放,有一个名为“android:layout_weight”的属性

下面的示例是根据synic在这个线程上的响应修改的,显示了一个占屏幕75%的按钮(权重=.25)和一个占剩余25%的文本视图(权重=.75)。

<LinearLayout android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal">

    <Button android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight=".25"
        android:text="somebutton">

    <TextView android:layout_width="fill_parent"
        android:layout_height="Wrap_content"
        android:layout_weight=".75">
</LinearLayout>

查找屏幕的宽度和高度:

width = getWindowManager().getDefaultDisplay().getWidth();
height = getWindowManager().getDefaultDisplay().getHeight();

使用这个,我们可以获得最新的和更高版本的SDK 13。

// New width and height
int version = android.os.Build.VERSION.SDK_INT;
Log.i("", " name == "+ version);
Display display = getWindowManager().getDefaultDisplay();
int width;
if (version >= 13) {
    Point size = new Point();
    display.getSize(size);
    width = size.x;
    Log.i("width", "if =>" +width);
}
else {
    width = display.getWidth();
    Log.i("width", "else =>" +width);
}

首先加载XML文件,然后编写以下代码:

setContentView(R.layout.main);      
Display display = getWindowManager().getDefaultDisplay();
final int width = (display.getWidth());
final int height = (display.getHeight());

根据屏幕分辨率显示宽度和高度。

在Kotlin要简单得多。

val displayMetrics = Resources.getSystem().displayMetrics
displayMetrics.heightPixels
displayMetrics.widthPixels