android viewgroup

Main.xmlMainactivityPackage Com.example.simplelayout;import Android.app.activity;import Android.os.bundle;public class MainActivity Extends Activity { @Override public void OnCreate (Bundle savedinstancestate) { super.oncreate ( Savedinstancestate); Setcontentview (R.layout.main); }}MylinlayoutPackage Com.example.simplelayout;import Android.content.context;import Android.util.attributeset;import Android.view.view;import android.view.viewgroup;/** * onmeasure (): Measure yo

Below is the source code of Removeallviewsinlayout ()/** * Called by a viewgroup subclass to remove child views from itself, * when it must first know its size on scre En before it can calculate how many * child views it would render. An example was a Gallery or a ListView, which * may "has" children, but actually only render the number of children * That can currently fit inside the object in screen. Do not call * This method unless you is exten

NewIllegalArgumentException ("Cannot add a null child view to a ViewGroup"); }//Addviewinner () would call Child.requestlayout () when setting the new Layoutparams //Therefore, we call Requestlayout () on ourselves before, so that's the child's request // would be blocked at our level1. Requestlayout (); 2. Invalidate (true); Addviewinner (Child, Index,params,false); }See the 1.2 of my logo?Explanation of 1:When view determines that it

class Scrolltextview extends ViewGroup {private static final int SCROLL = 0;private static final int JUSTIFY = 1;private static final int animation_duration = 3000;privat e int morientation;private int msize;private int mindex;private int mposition;private Scroller mscroller;private Map Getmeasuredwidth (): Getmeasuredheight (); if (flag text!=null) {int length = Text.length (); LOG.I ("AAA", "Length*textsize:" +length*textsize+ "Measuredwidth:" +

Design Requirements:ViewGroup There are two View,viewa, VIEWB, need two view all display in the screen range of ViewGroup, do not allow the growth of Viewa will make VIEWB extrude the screen, which requires viewb allow stretching does not allow contraction, and Viewa is contracted. The process is as follows:when the Viewa shrinks, the VIEWB follows the stretch::when the Viewa width is too long, assuming 9000DP or greater, VIEWB is not allowed to shrin

Solve the problem that ViewGroup does not call onDraw (), viewgroupondraw Today, when I was working on a project, I customized a View that inherits LinearLayout. As a result, the onDraw () method in the result cannot be called. Later, we found that ViewGroup does not call the onDraw () method by default. The reason is that we will not go into it for the moment. There is a very simple solution, that is, n

First: Poor animation effect ..... Code: package com.example.scrolltextview;import java.util.HashMap;import java.util.Iterator;import java.util.Map;import android.content.Context;import android.content.res.TypedArray;import android.graphics.Paint;import android.os.Handler;import android.os.Message;import android.util.AttributeSet;import android.util.Log;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.ArrayAdapter;impor

1. By default, the subview added to viewgrop is displayed directly. There is a relatively simple way to add an animation effect for this process.2. knowledge Point: The layoutanimationcontroller class is used to add animation effects to the sub-view. The layoutanimationcontroller must emphasize that different animation effects cannot be specified for each sub-view, however, the animation effect time can be displayed for each subview. 3. Example: The following shows how to add an animation effect

, assume that the custom view has two aligned buttons and a centered TextView, then the button and TextView object is first generated (Button BTN = n EW Button (context) | TextView TV = new TextView (context)); 7) After acquiring the object of the View Neutron view, add properties for the child view object, for example: Btn.settextcolor (Lefttextcolor);8) After the child view gets to the attribute, think about how to place the child view in the specified location? Use Layoutparams for position

Recently saw someone asked the meaning of these three parameters, in fact, help has been very detailed introduction of these three parameters, it seems to be good to learn English, or even explain can not understand./*** Get A View that displays the data on the specified position in the data set. You can either* Create a View manually or inflate it from an XML layout file. When the View is inflated, the* Parent View (GridView, ListView ...) would apply default layout parameters unless you use* {

For example, a horizontal viewgroup, if the width of each view is 300, then the first view is currently displayed when the GETSCROLLX () return value is 0, when you move the first view to the left, the distance is 30, then GETSCROLLX () The return value is 30, if the second view is currently displayed, then the return value of GETSCROLLX () is 300, the second view moves to the left a little, if the distance is 20, then the return value of GETSCROLLX (

Today's time is a little tight, a company organized by the Texas hold ' em to play, I will not say anything more. Just look at the effect first: Effect: Very simple is the center of the central image of the ring scattered! Core Logic: Obviously, this time is designed to place sub-view location, basic and the previous blog technical point is basically consistent, but also adopted the form of custom viewgroup, let the container add sub-view, and th

I use the top tab in the home page, that is, pages a open page B page B opens page C error, using the function but always error. Not allowed to load local Resource:file:///android_asset/webkit/android-web Solution: Can only say that the official demo is not very rigorous, so the key parameters have no notes, this parameter in fact this page ID, where this ID is set, the previous page opened this page. Method One, change the ID of this page.

Android, do you know how many layers will Crash after the interface layout is nested? androidcrash Let's first put a diagram of Hierarchy Viewer: (simulator Android4.4) Do you see the number 6? The RelativeLayout is the root ViewGroup of MainActivity, and there are 5 layers before RelativeLayout, that is, the default system interface DecorView (FrameLayout) --> LinearLayout --> FramelLayout --> ActionBarO

Android development, touch control everywhere. For some students do not see the source code, how many of this will have some doubts. View event distribution mechanism, not only in doing business requirements will encounter these problems, in some interview written questions are often asked, it is commonplace. I've also seen a lot of people write this article, not too long-winded is too vague, there are some in the details of the dispute is also writte

the draw () process. java // initiate the "poster" of draw () in viewroot. java's javasmtraversals () method. This method continues to call the draw () method to start drawing private void draw (){//... view mview; mview. draw (canvas );//....} // calls back the onlayout process in the view. This method is implemented only by the viewgroup type private void draw (canvas) {// This method will do the following: // 1. Draw the background of the view. //

Event distribution is a very important mechanism in Android and is the basis for user interaction with the interface. This article will create a flowchart of event distribution by using the example print log, making it easier for everyone to understand the Android event distribution mechanism. First, the necessary basic knowledge 1. Related methods The methods associated with event distribution in

TouchEvent touch event mechanism in Android When our Fingers click or slide on the Android screen, the touch event TouchEvent is triggered. In the App, ViewGroup and View have multi-level nesting. In the outermost layer, there are Activity and inner View, some viewgroups between Activity and View. To simplify the discussion, we assume that only one

Touch event TouchEvent is triggered when our fingers are clicked or slid on the Android screen. In the app, ViewGroup and view exist in multiple levels of nesting, in the outermost is activity, the most inner view, between activity and view is some viewgroup. To simplify the discussion, we assume that there is only one viewgr