Skip to main content

Improving Layout Performance

By


Improving Layout Performance

Layouts are a key part of Android applications that directly affect the user experience. If implemented poorly, your layout can lead to a memory hungry application with slow UIs. The Android SDK includes tools to help you identify problems in your layout performance, which when combined the lessons here, you will be able to implement smooth scrolling interfaces with a minimum memory footprint.
Lessons
Optimizing Layout Hierarchies
In the same way a complex web page can slow down load time, your layout hierarchy if too complex can also cause performance problems. This lesson shows how you can use SDK tools to inspect your layout and discover performance bottlenecks.
Re-using Layouts with <include/>
If your application UI repeats certain layout constructs in multiple places, this lesson shows you how to create efficient, re-usable layout constructs, then include them in the appropriate UI layouts.
Loading Views On Demand
Beyond simply including one layout component within another layout, you might want to make the included layout visible only when it's needed, sometime after the activity is running. This lesson shows how you can improve your layout's initialization performance by loading portions of your layout on demand.
Making ListView Scrolling Smooth
If you've built an instance of ListView that contains complex or data-heavy content in each list item, the scroll performance of the list might suffer. This lesson provides some tips about how you can make your scrolling performance more smooth.

Comments

Post a Comment

Popular posts from this blog

Custom camera using SurfaceView android with autofocus & auto lights & more

By
Custom camera using SurfaceView android with autofocus & auto lights & much more /**  * @author Tatyabhau Chavan  *  */ public class Preview extends SurfaceView implements SurfaceHolder.Callback {     private SurfaceHolder mHolder;     private Camera mCamera;     public Camera.Parameters mParameters;     private byte[] mBuffer;     private Activity mActivity;     // this constructor used when requested as an XML resource     public Preview(Context context, AttributeSet attrs) {         super(context, attrs);         init();     }     public Preview(Context context) {         super(context);         init();     }     public Camera getCamera() {         return this.mCamera;     }     public void init() {         // Install a SurfaceHolder.Callback so we get notified when the         // underlying surface is created and destroyed.         mHolder = getHolder();         mHolder.addCallback(this);         mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);     }     public
Post a Comment
click here

Get Android phone call history/log programmatically

By
Get Android phone call history/log programmatically To get call history programmatically first add read conact permission in Manifest file : <uses-permission android:name="android.permission.READ_CONTACTS" /> Create xml file. Add the below code in xml file : <Linearlayout android:layout_height="fill_parent"  android:layout_width="fill_parent" android:orientation="vertical"> <Textview android:id="@+id/call" android:layout_height="fill_parent" android:layout_width="fill_parent"> </Textview> </Linearlayout> Now call the getCallDetails() method in java class : private void getCallDetails() { StringBuffer sb = new StringBuffer(); Cursor managedCursor = managedQuery( CallLog.Calls.CONTENT_URI,null, null,null, null); int number = managedCursor.getColumnIndex( CallLog.Calls.NUMBER ); int type = managedCursor.getColumnIndex( CallLog.Calls.TYPE ); int date = managedCur
1 comment
click here

Bitmap scalling and cropping from center

By
How to Bitmap scalling and cropping from center? public class ScalingUtilities {     /**      * Utility function for decoding an image resource. The decoded bitmap will      * be optimized for further scaling to the requested destination dimensions      * and scaling logic.      *      * @param res      *            The resources object containing the image data      * @param resId      *            The resource id of the image data      * @param dstWidth      *            Width of destination area      * @param dstHeight      *            Height of destination area      * @param scalingLogic      *            Logic to use to avoid image stretching      * @return Decoded bitmap      */     public static Bitmap decodeResource(Resources res, int resId, int dstWidth,             int dstHeight, ScalingLogic scalingLogic) {         Options options = new Options();         options.inJustDecodeBounds = true;         BitmapFactory.decodeResource(res, resId, options);
Post a Comment
click here