Analysis of Motionevent coordinate acquisition method in Android development _android

This paper illustrates the Motionevent coordinate acquisition method in Android development. Share to everyone for your reference, specific as follows:

The Android motionevent getx () and GETRAWX () are all getting screen coordinates (horizontal), but there's a difference
GetX (): is the coordinate to get relative to the current control (View)
GETRAWX (): Gets the coordinates of the upper-left corner of the display screen

Demo Sample Code

Java code:

public class Mainactivity extends activity implements Ontouchlistener {
  private Button btn;
  private int x = 0, y = 0;
  private int rawx = 0, Rawy = 0;
  @Override
  protected void onCreate (Bundle savedinstancestate) {
    super.oncreate (savedinstancestate);
    Setcontentview (r.layout.main);
    BTN = (Button) Findviewbyid (R.ID.BTN);
    Btn.setontouchlistener (this);
  }
  @Override Public
  Boolean Ontouch (view view, Motionevent event) {
    int eventaction = Event.getaction ();
    Switch (eventaction) {case
    motionevent.action_down: Break
      ;
    Case Motionevent.action_move:
      x = (int) event.getx ();
      y = (int) event.gety ();
      RAWX = (int) event.getrawx ();
      Rawy = (int) event.getrawy ();
      LOG.E ("Homer", "x =" + x +); y = "+ y +"; RAWX = "+ Rawx +"; Rawy = "+ Rawy);
      break;
    Case MOTIONEVENT.ACTION_UP: Break
      ;
    }
    return false;
  }
}

XML code:

<relativelayout xmlns:android= "http://schemas.android.com/apk/res/android"
  xmlns:tools= "http:// Schemas.android.com/tools "
  android:layout_width=" fill_parent "
  android:layout_height=" Fill_parent
  " Tools:context= ". Mainactivity ">
  <textview
    android:id=" @+id/txt "
    android:layout_width=" Wrap_content " android:layout_height= "Wrap_content"
    android:layout_centerhorizontal= "true"
    android:layout_ Centervertical= "true"
    android:text= "@string/hello_world"/>
  <button android:id=
    "@+id/btn"
    android:layout_width= "wrap_content"
    android:layout_height= "wrap_content"
    android:layout_below= "@id/txt"
    android:layout_centerinparent= "true"
    android:text= "button Me"/>
</relativelayout >

Run Result:

Click the button in the middle of the screen to get the coordinate information:

Results show:

X,y: The coordinate GetX () of the relative button controls obtained separately, GetY ()
Rawx,rawy: The coordinates of the upper-left corner of the display screen are obtained separately getrawx (), Getrawy ()

Summarize:

GetX () is the x-coordinate that represents the widget relative to its upper-left corner. The GETRAWX () is the x-coordinate relative to the upper-left corner of the screen (note: The upper-left corner of the screen is the upper left of the phone screen, regardless of whether the activity is titlebar or full screen); GetY (), Getrawy () The same truth

More readers interested in Android-related content can view this site: Android Development Primer and Advanced tutorial, Android mobile phone information How-to summary, Android resource Operation tips Summary and Android Basic component Usage Summary

I hope this article will help you with the Android program.