Today, the project has a demand, class is a function within the QQ space, so the study of a bit, well, say so much, there may be people who do not know the point is that, directly on. Forgive me for not making a dynamic diagram:
Yes, that is the effect, I studied, the idea is as follows: 1. Monitor the slide of the ScrollView 2. By judging the sliding distance, and then setting the corresponding color gradient to titlebar but then I found that I could not find the ScrollView listener, that is to say, ScrollView does not provide the corresponding monitoring interface, do not provide even if it, I myself provided the following code: package com.example.myscrollview; import android.content.Context;import android.util.AttributeSet;import android.view.View;import android.widget.scrollview; public class myscrollview extends scrollview { private ScrollViewListener scrollViewListener = null; public myscrollview (Context context) { super (context); } public myscrollview (context) context, attributeset attrs) { super ( Context, attrs); } @Override Protected void onscRollchanged (Int x, int y, int oldx, int oldy) { // x is the horizontal axis of the current slider, y represents the ordinate of the current slider, OLDX is the horizontal axis of the previous slide, and the oldy represents the vertical axis of the previous slide super.onscrollchanged (X, y, oldx, oldy); if (scrollviewlistener != null) { // to expose the method here scrollviewlistener.onscrollchanged (This, x, y, oldx, oldy); } } // Do you want its elastic sliding @Override protected boolean Overscrollby (int deltax, int deltay, int scrollx, int scrolly, int scrollrangex, int scrollrangey, int maxOverScrollX, int maxOverScrollY, boolean istouchevent) { // Elastic sliding key is maxoverscrollx, and maxoverscrolly, // The general default value is 0, when elasticity is required, change its value // that is, zero is not elastic, not 0 (>0, negative number not tested) will slide to its value position return super.overscrollby (deltax, deltay, scrollx, scrolly, scrollrangex, scrollrangey, 0, 0, istouchevent); } Interfaces public interface ScrollViewListener { vOid onscrollchanged (View scrollview, int x, int y, int oldx, int oldy); } public void Setscrollviewlistener (Scrollviewlistener listener) { Once the scrollviewlistener = listener; }} customization is complete, it can be obtained in the mainactivity: package com.example.myscrollview; import android.app.Activity;import android.os.bundle;import android.view.view;import android.widget.relativelayout; import com.example.myscrollview.myscrollview.scrollviewlistener; public class mainactivity extends activity { myscrollview scroll; relativelayout title; @Override protected void oncreate (bundle savedinstancestate) &NBSP;{&NBSP;&NBsp; super.oncreate (savedinstancestate); setcontentview (R.layout.activity_main); scroll = (Myscrollview) findviewbyid (r.id.scroll); title = (relativelayout) findviewbyid (r.id.title); // implementing a listener in a custom control Scroll.setscrollviewlistener (New scrollviewlistener () { @Override public void onscrollchanged (View scrollview, int x, int y, int oldx, int oldy) { // TODO auto-generated method stub titleanima (y); } }); } /** * Gradient Effects */ Public void titleanima (int y) { int Scrollheight = scroll.getchildat (0). GetHeight () - scroll.getheight (); float scrollPercent = (float) y / scrollHeight; Title.getbackground (). Setalpha ((int) (255 * scrollpercent)); // If you have text, you can also set the color gradient of the text // Int color = toptext.gettextcolors (). Getdefaultcolor (); // int r = color.red (Color); // int g = color.green (Color); // int b = color.blue (Color); // int Changetocolor = color.argb ((int) (255 * (1 - scrollpercent)), r, &NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;//&NBSP;G,&NBSP;B); / / toptext.settextcolor (changetocolor); } } My layout file activity_ Main.xml is like this: &NBSP;<RELATIVELAYOUT&NBsp;xmlns:android= "Http://schemas.android.com/apk/res/android" android:layout_width= " Match_parent " android:layout_height=" Match_parent " > <relativelayout android:id= "@+id/title" android:layout_width= "Match_parent" android:layout_height= "48DP" android:layout_ Alignparenttop= "true" android:background= "@android: Color/holo_ Red_dark " > <TextView android:layout_width= "Match_parent" android:layout_height= "Wrap_content" android:gravity= "Center_horizontal" android:text= "title" /> </RelativeLayout> <com.example.myscrollview.myscrollview android: Id= "@+id/scroll" android:layout_below= "@id/title" android:layout_width= "Match_parent" android:layout_height= "Match_parent" > <relativelayout android:layout _width= "Match_parent" android:layout_ height= "Match_parent" > <linearlayout &nBsp; android:id= "@+id/lin" android:layout_width = "Match_parent" android:layout_height= "Wrap_content" android:orientation= "Vertical" > <TextView android:layout_width = "Match_parent" android:layout_height= "Wrap_content" &Nbsp; android:background= "#fff" android:padding= "16DP" android:text= " HH Adi and France Hius big Hiugfhsdiuhgudhsiuahiudshfuihdsiuhhfsdkjhuiagfhsduiah speed up Kazakhstan, not to mention the Jiangsu work remember the calligrapher to speed up the struggle to fight Kazakhstan Rebel center Register card hh " android:textsize= "40SP" /> <TextView android:layout_width= "Match_parent" Android: layout_height= "Wrap_content" android:background= "#fff" android:padding= "16DP" android:text= " HH Adi and France Hius big Hiugfhsdiuhgudhsiuahiudshfuihdsiuhhfsdkjhuiagfhsduiah speed up Kazakhstan, not to mention the Jiangsu work remember the calligrapher to speed up the struggle to fight Kazakhstan Rebel center Register card hh " android:textsize= "40SP" /> <TextView android:layout_width= "Match_parent" &Nbsp; android:layout_ height= "Wrap_content" android:background= "#fff" android:padding= "16DP" Android:text= " HH Adi and France Hius big Hiugfhsdiuhgudhsiuahiudshfuihdsiuhhfsdkjhuiagfhsduiah speed up Kazakhstan, not to mention the Jiangsu work remember the calligrapher to speed up the struggle to fight Kazakhstan Rebel center Register card hh " android:textsize= "40SP" /> <TextView android:layout_width= "Match_parent" android:layout_ height= "Wrap_content" android:background= "#fff" android:padding= "16DP" Android:text= " HH Adi and France Hius big Hiugfhsdiuhgudhsiuahiudshfuihdsiuhhfsdkjhuiagfhsduiah speed up Kazakhstan, not to mention the Jiangsu work remember the calligrapher to speed up the struggle to fight Kazakhstan Rebel center Register card hh " android:textsize= "40SP" /> </linearlayout> </relativelayout> </ com.example.myscrollview.myscrollview> </relativelayout> is not very simple, do not thank, please call me Lei Feng.
The titlebar state changes with ScrollView sliding in Android
