Android_imageview simple implementation of picture flipping

1) The ID of the image can be stored in an array , using setimageresource () or setimagedrawable () Method ( put in an array for easy looping )

2 ) already the first image, then click on the "previous page", should Toast tip : is already the first image , no further forward; an image, then click on "Next", you should Toast tip : It is the last image , and no more to turn back.

Give the source code

<?xml version= "1.0" encoding= "Utf-8"? ><framelayout xmlns:android= "Http://schemas.android.com/apk/res/android"Xmlns:app= "Http://schemas.android.com/apk/res-auto"Xmlns:tools= "Http://schemas.android.com/tools"Android:layout_width= "Match_parent"Android:layout_height= "Match_parent"android:orientation= "Horizontal"Tools:context= "com.example.asus.a161304049_gary03." Mainactivity "> <LinearLayout Android:id= "@+id/layoutt"Android:layout_width= "Match_parent"Android:layout_height= "215DP"android:orientation= "Vertical" > <ImageView Android:id= "@+id/imagexianshi"Android:layout_width= "Match_parent"Android:layout_height= "180DP"App:srccompat= "@drawable/qzu1"/> <LinearLayout android:layout_width= "Match_parent"Android:layout_height= "Match_parent"android:orientation= "Horizontal" > <Button Android:id= "@+id/back"Android:layout_width= "100DP"Android:layout_height= "Wrap_content"android:gravity= "Center"Android:text= "Previous"/> <Button Android:id= "@+id/next"Android:layout_width= "100DP"Android:layout_height= "Wrap_content"Android:text= "Next"/> </LinearLayout> </LinearLayout></FrameLayout>

Activity_main.xml

 Packagecom.example.asus.a161304049_gary03;Importandroid.support.v7.app.AppCompatActivity;ImportAndroid.os.Bundle;ImportAndroid.view.View;ImportAndroid.widget.ImageView;ImportAndroid.widget.Button;ImportAndroid.widget.Toast; Public classMainactivityextendsappcompatactivity {//use an array to save the picture       int[] Images =New int[]{r.drawable.qzu1, R.drawable.qzu2, R.DRAWABLE.QZU3, R.drawable.qzu5    }; //Subscript as a picture    intcountimg = 0; //buttons for forward and backward    PrivateButton b1,b2; //use ImageView to store pictures    PrivateImageView Xianshi; @Overrideprotected voidonCreate (Bundle savedinstancestate) {Super. OnCreate (savedinstancestate);        Setcontentview (R.layout.activity_main); B1=(Button) Findviewbyid (r.id.back); B2=(Button) Findviewbyid (R.id.next); Xianshi=(ImageView) Findviewbyid (R.id.imagexianshi); Xianshi.setimageresource (images[0]); B1.setonclicklistener (NewButton.onclicklistener () { Public voidOnClick (View v) {//Here's a simple logic .//If the selected picture is the first one, then you can no longer select the previous sheet. Messages that output toast prompts                if(countimg>0) {countimg--; //use Setimageresource to display picturesXianshi.setimageresource (images[countimg]); }Else{toast.maketext (mainactivity). This, "It's the first image, no more forward.", Toast.length_short). Show ();        }            }        }); B2.setonclicklistener (NewButton.onclicklistener () { Public voidOnClick (View v) {//If the selected picture is the last, then you cannot select the next one. Messages that output toast prompts                if(countimg<3) {countimg++;                Xianshi.setimageresource (images[countimg]); }Else{toast.maketext (mainactivity). This, "It's the last image and it's not going to turn back.", Toast.length_short). Show ();    }            }        }); }}

mainactivity

ImageView controls are used to store images, XML attributes are not the focus of this article, and are not described here.

First step: Define member variables

    // use an array to save the picture       int New int []{            r.drawable.qzu1,            r.drawable.qzu2,            r.drawable.qzu3,            r.drawable.qzu5    };     // Subscript as a picture    int countimg = 0;     // Buttons for forward and backward    Private Button b1,b2;     // use ImageView to store pictures    Private ImageView Xianshi;

Step two: Implement the event response mechanism of the button "previous" and "Next"

 protected voidonCreate (Bundle savedinstancestate) {Super. OnCreate (savedinstancestate);        Setcontentview (R.layout.activity_main); B1=(Button) Findviewbyid (r.id.back); B2=(Button) Findviewbyid (R.id.next); Xianshi=(ImageView) Findviewbyid (R.id.imagexianshi); Xianshi.setimageresource (images[0]); B1.setonclicklistener (NewButton.onclicklistener () { Public voidOnClick (View v) {//Here's a simple logic .//If the selected picture is the first one, then you can no longer select the previous sheet. Messages that output toast prompts                if(countimg>0) {countimg--; //use Setimageresource to display picturesXianshi.setimageresource (images[countimg]); }Else{toast.maketext (mainactivity). This, "It's the first image, no more forward.", Toast.length_short). Show ();        }            }        }); B2.setonclicklistener (NewButton.onclicklistener () { Public voidOnClick (View v) {//If the selected picture is the last, then you cannot select the next one. Messages that output toast prompts                if(countimg<3) {countimg++;                Xianshi.setimageresource (images[countimg]); }Else{toast.maketext (mainactivity). This, "It's the last image and it's not going to turn back.", Toast.length_short). Show ();    }            }        }); }

Portal: Message mode Toast.make Several common uses of text

Android_imageview simple implementation of picture flipping