Android Studio-MPAndroidChart将用户输入添加到折线图

Question

嘿，伙计们，这是我第一次使用MPandroidChart，我目前正在试用它，以充分了解如何使用它及其功能。目前，我正在尝试使用用户输入的数据(通过片段(更新我的折线图。我看到了一些关于堆栈溢出的类似问题，但它们似乎都不适用于我

任何帮助都将不胜感激。提前谢谢。

注意：有一些重复的代码，因为我在尝试并试图找出不同的方法来寻找解决方案。

获取用户输入的MainFragment

public class Fragment1 extends Fragment {
EditText Input;
Button EnterVal;
public float userInput;
//Fragment1Listener activityCommander;
public interface Fragment1Listener{
void sendInput(float value);
}
/*@Override
public void onAttach(Context context) {
super.onAttach(context);
try{
activityCommander = (Fragment1Listener) getTargetFragment();
}catch (ClassCastException e){
throw new ClassCastException(context.toString() + "Must Implement FragmentListener");
}
}*/
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment1, container, false);
//@SuppressWarnings("all")
Input = view.findViewById(R.id.Input);
EnterVal = view.findViewById(R.id.button);

EnterVal.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
String val = Input.getText().toString();
if(val != null && val.length() > 0) {
userInput = Float.valueOf(val);
Input.setText("");
/*if(activityCommander != null) {
activityCommander.sendInput(userInput);
}*/
Fragment1Listener listener = getListener();
if(listener != null){
listener.sendInput(userInput);
Log.d("User Val", "Listener was successfull!");
}
}
}
});
return view;
}
@Nullable
private Fragment1Listener getListener(){
Fragment1Listener activityCommander;
try{
Fragment onInputSelected_Frag = getTargetFragment();
if(onInputSelected_Frag != null){
activityCommander = (Fragment1Listener) onInputSelected_Frag;
}
else{
Activity onInputSelected_Act = getActivity();
activityCommander = (Fragment1Listener) onInputSelected_Act;
}
return activityCommander;
}catch(ClassCastException e){
Log.e("Fragment Listener", "getListener: ClassCastException + " + e.getMessage());
}
return null;
}
}

MPandroidchart片段(折线图(

public class Fragment2 extends Fragment implements Fragment1.Fragment1Listener{
private LineChart lineChart;
//public Fragment1 fragment1;
private ArrayList<ILineDataSet> DataSets = new ArrayList<>();
private LineDataSet lineDataSet5;
private ArrayList<Entry> userData = new ArrayList<>();
private LineData data = new LineData(DataSets);
@Override
public void sendInput(float value) {
data = lineChart.getData();
ILineDataSet xSet = data.getDataSetByIndex(0);
data.addEntry(new Entry(xSet.getEntryCount(), value),0);
//lineDataSet5.notifyDataSetChanged();
//lineDataSets.add(lineDataSet5);
data.notifyDataChanged();
lineChart.notifyDataSetChanged();
lineChart.invalidate();
lineChart.moveViewToX(data.getEntryCount());
}
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment2, container, false);
lineChart = view.findViewById(R.id.LineChart);
//Enable Touch Gestures
lineChart.setTouchEnabled(true);
//We want also enable scaling and dragging
lineChart.setDragEnabled(true);
lineChart.setScaleEnabled(true);
//Enable pinch zoom to avoid scaling x and y axis separately
lineChart.setPinchZoom(true);
//Double tap zoom to chart
lineChart.setDoubleTapToZoomEnabled(true);
//Alternate Background Color
lineChart.setBackgroundColor(Color.parseColor("#2b2b2b"));
ArrayList<String> xAXES = new ArrayList<>();
ArrayList<Entry> yAXESsin = new ArrayList<>();
ArrayList<Entry> yAXEScos = new ArrayList<>();
ArrayList<Entry> yAXEStan = new ArrayList<>();
ArrayList<Entry> random = new ArrayList<>();
double x = 0;
int numDataPoints = 1000;
for(int i =0; i<numDataPoints; i++){
float sinFunction = Float.parseFloat(String.valueOf(Math.sin(x)));
float cosFunction = Float.parseFloat(String.valueOf(Math.cos(x)));
float tanFunction = Float.parseFloat(String.valueOf(Math.tan(x)));
x += 0.1;
yAXESsin.add(new Entry(i, sinFunction));
yAXEScos.add(new Entry(i, cosFunction));
yAXEStan.add(new Entry(i, tanFunction));
xAXES.add(i, String.valueOf(x));
final int randomVal = getRandomNumber(-10, 10);
float randomData = (float) randomVal;
random.add(new Entry(i, randomData));
}
String[] xaxes = new String[xAXES.size()];
for(int i =0; i<xAXES.size(); i++){
xaxes[i] = xAXES.get(i).toString();
}
//Add user Input
//@SuppressWarnings("all")
//userInput = fragment1.getUserInput();
//userData.add(new Entry(userData.size()+1, userInput));
ArrayList<ILineDataSet> lineDataSets = new ArrayList<>();
ArrayList<ILineDataSet> dataSets = new ArrayList<>();
//Data Set 1
LineDataSet lineDataSet1 = new LineDataSet(yAXEScos, "Cos");
lineDataSet1.setAxisDependency(YAxis.AxisDependency.LEFT);
lineDataSet1.setDrawCircles(false);
lineDataSet1.setColor(Color.parseColor("#B71C1C"));
lineDataSet1.setLineWidth(3f);
lineDataSet1.setHighlightEnabled(true);
lineDataSet1.setDrawHighlightIndicators(true);
lineDataSet1.setHighLightColor(Color.parseColor("#FF4081"));
lineDataSet1.setValueTextSize(10f);
lineDataSet1.setValueTextColor(Color.WHITE);
lineDataSet1.setFillAlpha(110);
//Data Set 2
LineDataSet lineDataSet2 = new LineDataSet(yAXESsin, "Sin");
lineDataSet2.setAxisDependency(YAxis.AxisDependency.LEFT);
lineDataSet2.setDrawCircles(false);
lineDataSet2.setColor(Color.parseColor("#33bbff"));
lineDataSet2.setLineWidth(3f);
lineDataSet2.setHighlightEnabled(true);
lineDataSet2.setDrawHighlightIndicators(true);
lineDataSet2.setHighLightColor(Color.parseColor("#FFD600"));
lineDataSet2.setValueTextSize(10f);
lineDataSet2.setValueTextColor(Color.WHITE);
lineDataSet2.setFillAlpha(110);
//Data Set 3
LineDataSet lineDataSet3 = new LineDataSet(yAXEStan, "Tan");
lineDataSet3.setAxisDependency(YAxis.AxisDependency.LEFT);
lineDataSet3.setDrawCircles(false);
lineDataSet3.setColor(Color.parseColor("#FFD600"));
lineDataSet3.setLineWidth(3f);
lineDataSet3.setHighlightEnabled(true);
lineDataSet3.setDrawHighlightIndicators(true);
lineDataSet2.setHighLightColor(Color.parseColor("#FFD600"));
lineDataSet2.setValueTextSize(10f);
lineDataSet2.setValueTextColor(Color.WHITE);
lineDataSet2.setFillAlpha(110);
//Data Set 4
/*LineDataSet lineDataSet4 = new LineDataSet(random, "Random Numbers");
lineDataSet4.setAxisDependency(YAxis.AxisDependency.LEFT);
lineDataSet4.setDrawCircles(false);
lineDataSet4.setColor(Color.parseColor("#00897B"));
lineDataSet4.setLineWidth(3f);
lineDataSet4.setHighlightEnabled(true);
lineDataSet4.setDrawHighlightIndicators(true);
lineDataSet4.setHighLightColor(Color.parseColor("#64FFDA"));
lineDataSet4.setValueTextSize(10f);
lineDataSet4.setValueTextColor(Color.WHITE);
lineDataSet4.setFillAlpha(110);*/
//Data set 5 - User Input
lineDataSet5 = new LineDataSet(userData, "User Data");
lineDataSet5.setAxisDependency(YAxis.AxisDependency.LEFT);
lineDataSet5.setDrawCircles(false);
lineDataSet5.setColor(Color.parseColor("#9C27B0"));
lineDataSet5.setLineWidth(3f);
lineDataSet5.setHighlightEnabled(true);
lineDataSet5.setDrawHighlightIndicators(true);
lineDataSet5.setHighLightColor(Color.parseColor("#E040FB"));
lineDataSet5.setValueTextSize(10f);
lineDataSet5.setValueTextColor(Color.WHITE);
lineDataSet5.setFillAlpha(110);
//Add Data sets
lineDataSets.add(lineDataSet1);
lineDataSets.add(lineDataSet2);
lineDataSets.add(lineDataSet3);
//lineDataSets.add(lineDataSet4);
//lineDataSets.add(lineDataSet5);
lineChart.setData(new LineData(lineDataSets));
lineChart.setData(new LineData());
lineChart.setVisibleXRangeMaximum(65f);
lineChart.setHighlightPerTapEnabled(true);
//Get legend object
Legend legend = lineChart.getLegend();
//Customize Legend
legend.setForm(Legend.LegendForm.LINE);
legend.setTextColor(Color.WHITE);
//Set x axis
XAxis xAxis = lineChart.getXAxis();
xAxis.setPosition(XAxis.XAxisPosition.BOTTOM);
xAxis.setTextColor(Color.WHITE);
xAxis.setTextSize(10f);
xAxis.setDrawGridLines(true);
xAxis.setAvoidFirstLastClipping(true);
//Set y axis
YAxis yAxis = lineChart.getAxisLeft();
yAxis.setTextColor(Color.WHITE);
yAxis.setTextSize(10f);
yAxis.setDrawGridLines(true);
yAxis.setAxisMaximum(10f);
yAxis.setAxisMinimum(-10f);
//Disable Right y-axis values
lineChart.getAxisRight().setEnabled(false);
//Set Description
lineChart.getDescription().setText("Sin and Cos Functions");
lineChart.getDescription().setTextColor(Color.WHITE);
//Update and refresh for User Input
lineChart.notifyDataSetChanged(); //let the chart know it's data changed
lineChart.invalidate(); //Refresh
return view;
}
private int getRandomNumber(int min,int max) {
return (new Random()).nextInt((max - min) + 1) + min;
}
}

主要活动：

它管理两个选项卡，一个选项卡包含供用户输入其值的EditText，另一个选项卡则包含我想要更新的折线图。

public class MainActivity extends AppCompatActivity {
private SectionsPagerAdapter mSectionsPagerAdapter;
private ViewPager mViewPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
// Set up the ViewPager with the sections adapter.
mViewPager = findViewById(R.id.container);
//mViewPager.setAdapter(mSectionsPagerAdapter);
setupViewPager(mViewPager);
TabLayout tabLayout = findViewById(R.id.tabs);
tabLayout.setupWithViewPager(mViewPager);
mViewPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabLayout));
tabLayout.addOnTabSelectedListener(new TabLayout.ViewPagerOnTabSelectedListener(mViewPager));
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}
private void setupViewPager(ViewPager viewPager){
SectionsPagerAdapter adapter = new SectionsPagerAdapter(getSupportFragmentManager());
adapter.addFragment(new Fragment1(), "Fragment 1");
adapter.addFragment(new Fragment2(), "Fragment 2");
viewPager.setAdapter(adapter);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}

Answer 1

您可以更直接地设置侦听器。尝试将此方法添加到Fragment1(并删除getListener(

void setListener(Fragment1Listener listener) {
activityCommander = listener;
}

然后在"活动"中设置侦听器，如下

private void setupViewPager(ViewPager viewPager){
SectionsPagerAdapter adapter = new SectionsPagerAdapter(getSupportFragmentManager());
Fragment1 f1 = new Fragment1();
Fragment2 f2 = new Fragment2();
f1.setListener(f2);
adapter.addFragment(f1, "Fragment 1");
adapter.addFragment(f2, "Fragment 2");
viewPager.setAdapter(adapter);
}

当屏幕旋转时，这种方法可能会出现问题，但这至少会让你克服这个障碍。如果您想继续使用getTargetFragment方法，您也需要在某个地方调用setTargetFragment(请参阅此问题(。类似于上面代码中的f1.setTargetFragment(f2);而不是f1.setListener(f2)。

我认为，一旦监听器工作，您就需要对图形部分进行一些更改，以使其仍然工作。例如，更换

lineChart.setData(new LineData(lineDataSets));
lineChart.setData(new LineData()); // this overrides the previous line with an empty data set

带有

data.addDataSet([... the sets you want to add ...]);
lineChart.setData(data);

但这至少会让你走上正确的道路。