我正在制作一个滑块演练，当用户单击该应用程序时，该项就引入了应用程序中的第一项...。当用户再次打开它时，它就消失了。
像这样：https://www.youtube.com/watch?v=va2IRW_e7_w
问题是，每当我打开应用程序时，我都会一次又一次地重新获得它，这是一个小错误，我找不到它。
Main2Activity：
public class Main2Activity extends AppCompatActivity {
Button next, skip;
private ViewPagerAdapter adapter;
private ViewPager viewPager;
private SliderWalkthrough sliderWalkthrough;
private int[] layouts;
private TextView[] dots;
private LinearLayout dotsLayout;
ViewPager.OnPageChangeListener listener = new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
@Override
public void onPageSelected(int position) {
addButtonDots(position);
if (position == layouts.length - 1) {
next.setText("GET STARTED");
skip.setVisibility(View.GONE);
} else {
next.setText("NEXT");
skip.setVisibility(View.VISIBLE);
}
}
@Override
public void onPageScrollStateChanged(int state) {
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
sliderWalkthrough = new SliderWalkthrough(this);
if (!sliderWalkthrough.Check()) {
sliderWalkthrough.setFirst(false);
Intent intent = new Intent(Main2Activity.this, MainActivity.class);
startActivity(intent);
finish();
}
if (Build.VERSION.SDK_INT >= 21) {
getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
}
setContentView(R.layout.activity_main2);
viewPager = (ViewPager) findViewById(R.id.id_WalkThroughViewPager);
dotsLayout = (LinearLayout) findViewById(R.id.layout_dots);
layouts = new int[]{R.layout.slider_walkthrough_screen1, R.layout.slider_walkthrough_screen2, R.layout.slider_walkthrough_screen3};
addButtonDots(0);
adapter = new ViewPagerAdapter();
viewPager.setAdapter(adapter);
viewPager.addOnPageChangeListener(listener);
}
private void addButtonDots(int position) {
dots = new TextView[layouts.length];
int[] colorActive = getResources().getIntArray(R.array.active_dot);
int[] colorInactive = getResources().getIntArray(R.array.inactive_dot);
dotsLayout.removeAllViews();
for (int i = 0; i < dots.length; i++) {
dots[i] = new TextView(this);
dots[i].setTextSize(30);
dots[i].setTextColor(colorInactive[position]);
dotsLayout.addView(dots[i]);
}
if (dots.length > 0) {
dots[position].setTextColor(colorActive[position]);
}
}
}
SliderWalkthrough：
public class SliderWalkthrough {
SharedPreferences sharedPreferences;
SharedPreferences.Editor editor;
Context context;
public SliderWalkthrough(Context context) {
this.context = context;
sharedPreferences=context.getSharedPreferences("first",0);
editor=sharedPreferences.edit();
}
public void setFirst(Boolean firstTime){
editor.putBoolean("check",firstTime);
editor.commit();
}
public boolean Check()
{
return sharedPreferences.getBoolean("check",true);
}
}
最佳答案
演练完成后，您需要将preference值更改为false，否则将不会执行if (!sliderWalkthrough.Check()) {，并且每次都会显示演练
@Override
public void onPageSelected(int position) {
addButtonDots(position);
if (position == layouts.length - 1) {
next.setText("GET STARTED");
skip.setVisibility(View.GONE);
sliderWalkthrough.setFirst(false);
//^^^^^^ add this case
}
else {
next.setText("NEXT");
skip.setVisibility(View.VISIBLE);
}
}
注意：删除
sliderWalkthrough.setFirst(false);，不再需要 if (!sliderWalkthrough.Check()) {
Intent intent = new Intent(Main2Activity.this, MainActivity.class);
startActivity(intent);
finish();
}