Android Toolbar Follow the ListView sliding hidden and reality

Anyone who has used the Google Play store app or the app is aware that its actionbar can be hidden or displayed as the ListView slides. The effect looks very good, for this, I clumsily imitated a similar effect, do not know there is no better way.

First on the main layout activity_main:

<relativelayout xmlns:android= "http://schemas.android.com/apk/res/android"    xmlns:tools= "http// Schemas.android.com/tools "    android:layout_width=" match_parent "    android:layout_height=" Match_parent "    tools:context= "com.beak.music.ui.MainActivity" >    <listview        android:id= "@+id/main_list_view"        android:layout_width= "fill_parent"        android:layout_height= "fill_parent"        />    < Android.support.v7.widget.Toolbar        android:id= "@+id/main_bar"        android:layout_width= "Fill_parent"        android:layout_height= "wrap_content"        android:background= "@color/std_color_a"        /></ Relativelayout>

Note that the toolbar here, we will use this toolbar to replace the original Actionbar.

Now is the code in Mainactivity.java:

public class Mainactivity extends baseactivity{private static final String TAG = MainActivity.class.getSimpleName ();    Private Toolbar Mmaintoolbar = null;    Private ListView Mmainlistview = null;    private float Mstarty = 0, mlasty = 0, Mlastdeltay;        @Override protected void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate);        Setcontentview (R.layout.activity_main);        Mmaintoolbar = (Toolbar) This.findviewbyid (R.id.main_bar);        This.setsupportactionbar (Mmaintoolbar);        Mmainlistview = (ListView) This.findviewbyid (R.id.main_list_view);        Final View Header = Layoutinflater.from (this). Inflate (R.layout.layout_header, NULL);        Mmainlistview.addheaderview (header);        Mmainlistview.setadapter (New Audioadapter (this)); Mmainlistview.setontouchlistener (New View.ontouchlistener () {@Override public boolean OnTouch (View        V, motionevent event) {final float y = event.gety ();        float translationy = Mmaintoolbar.gettranslationy ();                         Switch (event.getaction ()) {case motionevent.action_down://log.v (TAG, ' down ');                        Mstarty = y;                        Mlasty = Mstarty;                    Break                        Case MotionEvent.ACTION_MOVE:float Mdeltay = y-mlasty;                        Float Newtansy = translationy + Mdeltay; if (newtansy <= 0 && newtansy >=-mmaintoolbar.getheight ()) {Mmaintoolbar.settra                        Nslationy (Newtansy);                        } mlasty = y;                        Mlastdeltay = mdeltay;//log.v (TAG, "Move");                    Break                        Case MotionEvent.ACTION_UP:ObjectAnimator animator = null;                 LOG.D (TAG, "mlastdeltay=" + Mlastdeltay);       if (Mlastdeltay < 0 && mmainlistview.getfirstvisibleposition () > 1) {Log.                            V (TAG, "listview.first=" + mmainlistview.getfirstvisibleposition ()); Animator = Objectanimator.offloat (Mmaintoolbar, "Translationy", Mmaintoolbar.gettranslationy (),-                        Mmaintoolbar.getheight ()); } else {animator = Objectanimator.offloat (Mmaintoolbar, "Translationy", Mmaintoolbar.gettransl                        Ationy (), 0);                        } animator.setduration (100);                        Animator.start (); Animator.setinterpolator (Animationutils.loadinterpolator (Mainactivity.this, Android.                        r.interpolator.linear));//LOG.V (TAG, "up");                Break            } return false;    }        }); }}

The main problem is the ListView swipe gesture detection and animation in toolbar.

First, with our own toolbar replace the original Actionbar, note, in your apptheme, Windowactionbar this item to be set to false in order to use our own to replace the original, or run will error, Then give the ListView a high Headerview such as toolbar. And then set up the touch event listener,

In the Action_move branch of the Ontouch method, we calculate the change in the position of our trigger point-mdeltay when the move event is triggered with the last move or down event, and then calculate a corresponding Translationy, After comparing with the toolbar height, judging whether the new translationy is lawful and lawful, the Settranslationy method is used to assign the value to toolbar.

To trigger the UP event:

When the up event is triggered, we need to use an animation to overdo it. First, the direction of the slide, the direction upward, then the upward slide, downward, then the downward movement.

Android Studio Project code codes here, but Android Studio code, no ADT code written

Android Toolbar Follow the ListView sliding hidden and reality