【发布时间】：2018-10-05 13:05:31
【问题描述】：
我正在创建一个闹钟应用程序，它在 MainActivity 上有一个闹钟列表，很像默认的 Android 时钟应用程序。为此，我实现了一个显示良好的 ListView。但是，我一直在尝试在 ListView 上设置一个更新按钮，以允许我通过我的 CreateAlarmActivity 更新警报的详细信息，并以此为指导：Intent in ListView。我已经检查了几次，但是当我在测试期间按下此按钮时，什么也没有发生。活动只是保持原样。
我确信这可能是一件简单而愚蠢的事情（几乎总是如此），但我似乎找不到我的错误。也许我需要 AlarmAdapter 的 onClick 方法以及 MainActivity 的 onItemClick 中的一些东西？
代码：
MainActivity.java
public class MainActivity extends AppCompatActivity {
ListView alarmListView;
ArrayList<Alarm> alarmList = new ArrayList<Alarm>();
AlarmAdapter alarmAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
alarmListView = findViewById(R.id.alarmListView);
// Credit to Mitch Woodbright for helping with this section, and other try/catch blocks.
try
{
ArrayList<Alarm> alarm = (ArrayList<Alarm>) getIntent().getSerializableExtra("alarmList");
for(Alarm elements : alarm){
alarmList.add(elements);
}
}
catch (NullPointerException e){
//error handling code
}
alarmAdapter = new AlarmAdapter(MainActivity.this, alarmList);
alarmListView.setAdapter(alarmAdapter);
alarmAdapter.notifyDataSetChanged();
alarmListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent updateAlarmIntent = new Intent(MainActivity.this, CreateAlarmActivity.class);
updateAlarmIntent.putExtra("alarmList", alarmList);
updateAlarmIntent.putExtra("position", position);
startActivity(updateAlarmIntent);
}
});
}
// Create alarm when user presses FAB on activity_main.xml.
public void createNewAlarm(View view) {
Intent createAlarmIntent = new Intent(this, CreateAlarmActivity.class);
createAlarmIntent.putExtra("alarmList", alarmList);
startActivity(createAlarmIntent);
}
public void testAlarmActivated(View view){
Intent activateAlarmIntent = new Intent(this, AlarmActivatedActivity.class);
startActivity(activateAlarmIntent);
}
}
CreateAlarmActivity.java
public class CreateAlarmActivity extends AppCompatActivity {
// If the alarm is being created, position = -1.
int position = -1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_create_alarm);
alarmList = (ArrayList<Alarm>)getIntent().getSerializableExtra("alarmList");
try {
// If we're updating an alarm, return the position of the alarm to update.
position = (int)getIntent().getSerializableExtra("position");
}
// Else, keep going.
catch (NullPointerException e){
}
}
int alarmHour = 6;
int alarmMinute = 0;
boolean isPm = false;
int snoozeTimer = 10;
int [] daysActive = new int[] {0, 0, 0, 0, 0, 0, 0};
ArrayList<Alarm> alarmList = new ArrayList<Alarm>();
// Add one to the hour of the alarm.
public void changeHour(View view) {
Button btn = findViewById(R.id.buttonHours);
if (alarmHour == 12){
alarmHour = 0;
}
else {
alarmHour++;
}
btn.setText(Integer.toString(alarmHour));
}
// Add one to the minute of the alarm.
public void changeMinute(View view) {
Button btn = findViewById(R.id.buttonMinutes);
if (alarmMinute == 59) {
alarmMinute = 0;
}
else {
alarmMinute++;
}
if (alarmMinute < 10) {
// Ensure minute 1 becomes 01, e.g, 6:01 am.
btn.setText("0" + Integer.toString(alarmMinute));
}
else {
btn.setText(Integer.toString(alarmMinute));
}
}
public void changeAmPm(View view) {
Button btn = findViewById(R.id.buttonAmPm);
if (isPm == true) {
isPm = false;
btn.setText("am");
}
else {
isPm = true;
btn.setText("pm");
}
}
public void changeSnoozeTimer(View view) {
Button btn = findViewById(R.id.buttonSnoozeTimer);
if (snoozeTimer == 15){
snoozeTimer = 1;
}
else {
snoozeTimer++;
}
btn.setText(Integer.toString(snoozeTimer));
}
public void finishAlarm(View view){
EditText alarmName = findViewById(R.id.alarmName);
String name = alarmName.getText().toString();
Alarm alarm = new Alarm(name, alarmHour, alarmMinute, isPm, daysActive, snoozeTimer);
// If we're creating an alarm.
if (position == -1) {
try {
alarmList.add(alarm);
} catch (Exception e) {
}
}
// Else, we're updating one.
else {
try {
// Set the alarm we're updating to the new alarm.
alarmList.set(position, alarm);
} catch (Exception e) {
}
}
Intent finishAlarmIntent = new Intent(this, MainActivity.class);
finishAlarmIntent.putExtra("alarmList", alarmList);
startActivity(finishAlarmIntent);
}
public void cancelAlarm(View view){
Intent cancelAlarmIntent = new Intent(this, MainActivity.class);
cancelAlarmIntent.putExtra("alarmList", alarmList);
startActivity(cancelAlarmIntent);
}
public void deleteAlarm(View view) {
// If creating a new alarm, deleting is the same as cancelling.
if (position == -1) {
cancelAlarm(view);
}
else {
// Remove the alarm.
alarmList.remove(position);
// Move each other alarm down one in the list.
for (int i = position; i < alarmList.size() - 1; i++){
Alarm tempAlarm = alarmList.get(i + 1);
alarmList.set(i, tempAlarm);
}
// Eliminate last item in the list, preventing duplicates.
alarmList.remove(alarmList.size() - 1);
}
}
public void changeSunday(View view) {
Button btn = findViewById(R.id.buttonSunday);
if (daysActive[0] == 0){
daysActive[0] = 1;
// Source: https://stackoverflow.com/questions/2173936/how-to-set-background-color-of-a-view
// Credit goes to EddieB for the below line.
btn.getBackground().setColorFilter(Color.parseColor("#00ff00"), PorterDuff.Mode.DARKEN);
}
else {
daysActive[1] = 0;
// Source: https://stackoverflow.com/questions/14802354/how-to-reset-a-buttons-background-color-to-default
// Credit goes to Ivo for the below line.
btn.getBackground().clearColorFilter();
}
}
public void changeMonday(View view) {
Button btn = findViewById(R.id.buttonMonday);
if (daysActive[1] == 0){
daysActive[1] = 1;
btn.getBackground().setColorFilter(Color.parseColor("#00ff00"), PorterDuff.Mode.DARKEN);
}
else {
daysActive[1] = 0;
btn.getBackground().clearColorFilter();
}
}
public void changeTuesday(View view) {
Button btn = findViewById(R.id.buttonTuesday);
if (daysActive[2] == 0){
daysActive[2] = 1;
btn.getBackground().setColorFilter(Color.parseColor("#00ff00"), PorterDuff.Mode.DARKEN);
}
else {
daysActive[2] = 0;
btn.getBackground().clearColorFilter();
}
}
public void changeWednesday(View view) {
Button btn = findViewById(R.id.buttonWednesday);
if (daysActive[3] == 0){
daysActive[3] = 1;
btn.getBackground().setColorFilter(Color.parseColor("#00ff00"), PorterDuff.Mode.DARKEN);
}
else {
daysActive[3] = 0;
btn.getBackground().clearColorFilter();
}
}
public void changeThursday(View view) {
Button btn = findViewById(R.id.buttonThursday);
if (daysActive[4] == 0){
daysActive[4] = 1;
btn.getBackground().setColorFilter(Color.parseColor("#00ff00"), PorterDuff.Mode.DARKEN);
}
else {
daysActive[4] = 0;
btn.getBackground().clearColorFilter();
}
}
public void changeFriday(View view) {
Button btn = findViewById(R.id.buttonFriday);
if (daysActive[5] == 0){
daysActive[5] = 1;
btn.getBackground().setColorFilter(Color.parseColor("#00ff00"), PorterDuff.Mode.DARKEN);
}
else {
daysActive[5] = 0;
btn.getBackground().clearColorFilter();
}
}
public void changeSaturday(View view) {
Button btn = findViewById(R.id.buttonSaturday);
if (daysActive[6] == 0){
daysActive[6] = 1;
btn.getBackground().setColorFilter(Color.parseColor("#00ff00"), PorterDuff.Mode.DARKEN);
}
else {
daysActive[6] = 0;
btn.getBackground().clearColorFilter();
}
}
}
AlarmAdapter.java
public class AlarmAdapter extends BaseAdapter{
private Context alarmContext;
private ArrayList<Alarm> alarmList;
public AlarmAdapter(Context context, ArrayList arrayList) {
super();
alarmContext = context;
alarmList = arrayList;
}
public int getCount() {
try{
return alarmList.size();
}catch(Exception e){
return 0;
}
}
// getView method is called for each item of ListView
public View getView(int position, View view, ViewGroup parent) {
// inflate the layout for each item of listView
LayoutInflater inflater = (LayoutInflater) alarmContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = inflater.inflate(R.layout.alarm_row, parent, false);
// get the reference of textView and button
TextView alarmName = (TextView) view.findViewById(R.id.listRowAlarmName);
TextView alarmTime = view.findViewById(R.id.listRowAlarmTime);
TextView alarmAmPm = view.findViewById(R.id.listRowAlarmAmPm);
TextView alarmDaysActive = view.findViewById(R.id.listRowAlarmDaysActive);
TextView alarmSnoozeTimer = view.findViewById(R.id.listRowAlarmSnoozeTimer);
Button updateButton = (Button) view.findViewById(R.id.listRowAlarmUpdate);
// Set the title and button name
Alarm tempAlarm = alarmList.get(position);
alarmName.setText(tempAlarm.name);
// Set minute if 0-9 to 00-09.
String minute = Integer.toString(tempAlarm.minute);
if (tempAlarm.minute < 10){
minute = "0" + minute;
}
alarmTime.setText(tempAlarm.hour + ":" + minute);
// Set AM or PM based on Boolean.
if (tempAlarm.isPm == true){
alarmAmPm.setText("PM");
}
else {
alarmAmPm.setText("AM");
}
// Figure out best way to change color of letters in text based on daysActive.
alarmSnoozeTimer.setText("Snooze Timer: " + tempAlarm.snoozeTimer + " minutes");
//updateButton.setText("Action " + position);
// Click listener of button
// Do I need this, since I'm overriding it in MainActivity? Find out.
updateButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
// Logic goes here.
}
});
return view;
}
public Object getItem(int position) {
// TODO Auto-generated method stub
return position;
}
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}}
alarm_row.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="96dp"
android:orientation="horizontal"
android:padding="5dip">
<TextView
android:id="@+id/listRowAlarmName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_alignParentEnd="true"
android:layout_marginStart="10dp"
android:layout_marginTop="5dp"
android:layout_toEndOf="@+id/listRowAlarmAmPm"
android:text="Name of Alarm"
android:textSize="18sp" />
<TextView
android:id="@+id/listRowAlarmTime"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true"
android:layout_marginStart="8dp"
android:layout_marginTop="4dp"
android:text="TIME"
android:textSize="28sp" />
<TextView
android:id="@+id/listRowAlarmDaysActive"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/listRowAlarmName"
android:layout_marginStart="10dp"
android:layout_toEndOf="@+id/listRowAlarmAmPm"
android:text="S M T W T F S"
android:textSize="18sp" />
<TextView
android:id="@+id/listRowAlarmAmPm"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_marginStart="8dp"
android:layout_marginTop="4dp"
android:layout_toEndOf="@+id/listRowAlarmTime"
android:text="PM"
android:textSize="28sp" />
<TextView
android:id="@+id/listRowAlarmSnoozeTimer"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/listRowAlarmDaysActive"
android:layout_marginStart="10dp"
android:layout_toEndOf="@+id/listRowAlarmAmPm"
android:text="Snooze Timer: N minutes"
android:textSize="16sp" />
<Button
android:id="@+id/listRowAlarmUpdate"
android:layout_width="133dp"
android:layout_height="42dp"
android:layout_below="@+id/listRowAlarmName"
android:layout_marginTop="13dp"
android:layout_marginEnd="-52dp"
android:layout_toStartOf="@+id/listRowAlarmAmPm"
android:text="Update"
android:textSize="16sp" />
</RelativeLayout>
【问题讨论】：
-
Jay，从 Adapter 类中删除该按钮单击侦听器并尝试单击行而不是按钮。请检查行单击是否允许您移动到下一个活动。请检查。
-
嗨帕鲁尔。从 Adapter 类中注释掉监听器后，单击该行（和按钮）不允许我移动到下一个活动。