Fix x-axis labels overlapping

MPChartLib/src/main/java/com/github/mikephil/charting/components/XAxis.java

@@ -47,6 +47,11 @@ public class XAxis extends AxisBase {
  */
  private boolean mAvoidFirstLastClipping = false;
 
+ /**
+ * minimum spacing between labels in pixels
+ */
+ protected float mSpaceBetweenLabelsMin = 0;
+
  /**
  * the position of the x-labels relative to the chart
  */
@@ -65,6 +70,19 @@ public XAxis() {
  mYOffset = Utils.convertDpToPixel(4.f); // -3
  }
 
+ /**
+ * Returns minimum spacing between labels in pixels
+ */
+ public float getSpaceBetweenLabelsMin() { return mSpaceBetweenLabelsMin; }
+
+ /**
+ * Sets minimum spacing between labels in pixels
+ */
+ public void setSpaceBetweenLabelsMin(float space)
+ {
+ mSpaceBetweenLabelsMin = space;
+ }
+
  /**
  * returns the position of the x-labels
  */

MPChartLib/src/main/java/com/github/mikephil/charting/renderer/AxisRenderer.java

@@ -7,7 +7,6 @@
 import android.graphics.Paint.Style;
 
 import com.github.mikephil.charting.components.AxisBase;
-import com.github.mikephil.charting.utils.MPPointD;
 import com.github.mikephil.charting.utils.Transformer;
 import com.github.mikephil.charting.utils.Utils;
 import com.github.mikephil.charting.utils.ViewPortHandler;
@@ -115,73 +114,26 @@ public Transformer getTransformer() {
  * @param min - the minimum value in the data object for this axis
  * @param max - the maximum value in the data object for this axis
  */
- public void computeAxis(float min, float max, boolean inverted) {
+ public abstract void computeAxis(float min, float max, boolean inverted);
 
- // calculate the starting and entry point of the y-labels (depending on
- // zoom / contentrect bounds)
- if (mViewPortHandler != null && mViewPortHandler.contentWidth() > 10 && !mViewPortHandler.isFullyZoomedOutY()) {
-
- MPPointD p1 = mTrans.getValuesByTouchPoint(mViewPortHandler.contentLeft(), mViewPortHandler.contentTop());
- MPPointD p2 = mTrans.getValuesByTouchPoint(mViewPortHandler.contentLeft(), mViewPortHandler.contentBottom());
-
- if (!inverted) {
-
- min = (float) p2.y;
- max = (float) p1.y;
- } else {
-
- min = (float) p1.y;
- max = (float) p2.y;
- }
-
- MPPointD.recycleInstance(p1);
- MPPointD.recycleInstance(p2);
- }
-
- computeAxisValues(min, max);
- }
 
  /**
- * Sets up the axis values. Computes the desired number of labels between the two given extremes.
- *
- * @return
+ * Compute axis interval and desired number of labels between the two given extremes
+ * @param min
+ * @param max
  */
- protected void computeAxisValues(float min, float max) {
-
- float yMin = min;
- float yMax = max;
-
- int labelCount = mAxis.getLabelCount();
- double range = Math.abs(yMax - yMin);
-
- if (labelCount == 0 || range <= 0 || Double.isInfinite(range)) {
- mAxis.mEntries = new float[]{};
- mAxis.mCenteredEntries = new float[]{};
- mAxis.mEntryCount = 0;
- return;
- }
-
- // Find out how much spacing (in y value space) between axis values
- double rawInterval = range / labelCount;
- double interval = Utils.roundToNextSignificant(rawInterval);
-
- // If granularity is enabled, then do not allow the interval to go below specified granularity.
- // This is used to avoid repeated values when rounding values for display.
- if (mAxis.isGranularityEnabled())
- interval = interval < mAxis.getGranularity() ? mAxis.getGranularity() : interval;
-
- // Normalize interval
- double intervalMagnitude = Utils.roundToNextSignificant(Math.pow(10, (int) Math.log10(interval)));
- int intervalSigDigit = (int) (interval / intervalMagnitude);
- if (intervalSigDigit > 5) {
- // Use one order of magnitude higher, to avoid intervals like 0.9 or 90
- // if it's 0.0 after floor(), we use the old value
- interval = Math.floor(10.0 * intervalMagnitude) == 0.0
- ? interval
- : Math.floor(10.0 * intervalMagnitude);
-
- }
+ protected abstract void computeAxisInterval(float min, float max);
 
+ /**
+ * Setup axis entries and decimals based on the previously computed interval and labels count
+ * @param min
+ * @param max
+ * @param labelCount
+ * @param range
+ * @param interval
+ */
+ protected void computeAxisValues(float min, float max, int labelCount, double range, double interval) {
+
  int n = mAxis.isCenterAxisLabelsEnabled() ? 1 : 0;
 
  // force label count
@@ -207,12 +159,12 @@ protected void computeAxisValues(float min, float max) {
  // no forced count
  } else {
 
- double first = interval == 0.0 ? 0.0 : Math.ceil(yMin / interval) * interval;
+ double first = interval == 0.0 ? 0.0 : Math.ceil(min / interval) * interval;
  if(mAxis.isCenterAxisLabelsEnabled()) {
  first -= interval;
  }
 
- double last = interval == 0.0 ? 0.0 : Utils.nextUp(Math.floor(yMax / interval) * interval);
+ double last = interval == 0.0 ? 0.0 : Utils.nextUp(Math.floor(max / interval) * interval);
 
  double f;
  int i;
@@ -262,7 +214,7 @@ else if (last == first && n == 0) {
  }
  }
  }
-
+ 
  /**
  * Draws the axis labels to the screen.
  *

MPChartLib/src/main/java/com/github/mikephil/charting/renderer/XAxisRenderer.java

@@ -45,7 +45,7 @@ public void computeAxis(float min, float max, boolean inverted) {
 
  // calculate the starting and entry point of the y-labels (depending on
  // zoom / contentrect bounds)
- if (mViewPortHandler.contentWidth() > 10 && !mViewPortHandler.isFullyZoomedOutX()) {
+ if (mViewPortHandler != null && mViewPortHandler.contentWidth() > 10 && !mViewPortHandler.isFullyZoomedOutX()) {
 
  MPPointD p1 = mTrans.getValuesByTouchPoint(mViewPortHandler.contentLeft(), mViewPortHandler.contentTop());
  MPPointD p2 = mTrans.getValuesByTouchPoint(mViewPortHandler.contentRight(), mViewPortHandler.contentTop());
@@ -64,14 +64,59 @@ public void computeAxis(float min, float max, boolean inverted) {
  MPPointD.recycleInstance(p2);
  }
 
- computeAxisValues(min, max);
+ computeAxisInterval(min, max);
  }
 
  @Override
- protected void computeAxisValues(float min, float max) {
- super.computeAxisValues(min, max);
+ protected void computeAxisInterval(float min, float max) {
 
+ // Compute the longest label width first
  computeSize();
+
+ int labelCount = mXAxis.getLabelCount();
+ double range = Math.abs(max - min);
+
+ if (labelCount == 0 || range <= 0 || Double.isInfinite(range)) {
+ mXAxis.mEntries = new float[]{};
+ mXAxis.mCenteredEntries = new float[]{};
+ mXAxis.mEntryCount = 0;
+ return;
+ }
+
+ // Find out how much spacing (in x value space) between axis values
+ double rawInterval = range / labelCount;
+ double interval = Utils.roundToNextSignificant(rawInterval);
+
+ // Do not allow the interval go below the label width with spacing.
+ double labelMaxWidth = (mXAxis.mLabelRotatedWidth + mXAxis.getSpaceBetweenLabelsMin()) * range / mViewPortHandler.contentWidth();
+ if (interval < labelMaxWidth)
+ interval = labelMaxWidth;
+
+ // If granularity is enabled, then do not allow the interval to go below specified granularity.
+ // This is used to avoid repeated values when rounding values for display.
+ if (mXAxis.isGranularityEnabled())
+ interval = interval < mXAxis.getGranularity() ? mXAxis.getGranularity() : interval;
+
+ // Perform rounding once again after interval was probably adjusted by label width and/or granularity checks.
+ rawInterval = interval;
+ interval = Utils.roundToNextSignificant(rawInterval);
+
+ // Normalize interval
+ double intervalMagnitude = Utils.roundToNextSignificant(Math.pow(10, (int) Math.log10(interval)));
+ int intervalSigDigit = (int) (interval / intervalMagnitude);
+ if (intervalSigDigit > 5) {
+ // Use one order of magnitude higher, to avoid intervals like 0.9 or 90
+ // if it's 0.0 after floor(), we use the old value
+ interval = Math.floor(10.0 * intervalMagnitude) == 0.0
+ ? interval
+ : Math.floor(10.0 * intervalMagnitude);
+
+ // If rounded down to current significant, round up to avoid label overlapping
+ } else if (interval < rawInterval) {
+ interval = (intervalSigDigit + 1) * intervalMagnitude;
+ }
+
+ computeAxisValues(min, max, labelCount, range, interval);
  }
 
  protected void computeSize() {
@@ -91,7 +136,6 @@ protected void computeSize() {
  labelHeight,
  mXAxis.getLabelRotationAngle());
 
-
  mXAxis.mLabelWidth = Math.round(labelWidth);
  mXAxis.mLabelHeight = Math.round(labelHeight);
  mXAxis.mLabelRotatedWidth = Math.round(labelRotatedSize.width);

MPChartLib/src/main/java/com/github/mikephil/charting/renderer/XAxisRendererHorizontalBarChart.java

@@ -55,7 +55,7 @@ public void computeAxis(float min, float max, boolean inverted) {
  MPPointD.recycleInstance(p2);
  }
 
- computeAxisValues(min, max);
+ computeAxisInterval(min, max);
  }
 
  @Override

MPChartLib/src/main/java/com/github/mikephil/charting/renderer/YAxisRenderer.java

@@ -41,6 +41,69 @@ public YAxisRenderer(ViewPortHandler viewPortHandler, YAxis yAxis, Transformer t
  }
  }
 
+ @Override
+ public void computeAxis(float min, float max, boolean inverted) {
+
+ // calculate the starting and entry point of the y-labels (depending on
+ // zoom / contentrect bounds)
+ if (mViewPortHandler != null && mViewPortHandler.contentWidth() > 10 && !mViewPortHandler.isFullyZoomedOutY()) {
+
+ MPPointD p1 = mTrans.getValuesByTouchPoint(mViewPortHandler.contentLeft(), mViewPortHandler.contentTop());
+ MPPointD p2 = mTrans.getValuesByTouchPoint(mViewPortHandler.contentLeft(), mViewPortHandler.contentBottom());
+
+ if (!inverted) {
+
+ min = (float) p2.y;
+ max = (float) p1.y;
+ } else {
+
+ min = (float) p1.y;
+ max = (float) p2.y;
+ }
+
+ MPPointD.recycleInstance(p1);
+ MPPointD.recycleInstance(p2);
+ }
+
+ computeAxisInterval(min, max);
+ }
+
+ @Override
+ protected void computeAxisInterval(float min, float max) {
+
+ int labelCount = mYAxis.getLabelCount();
+ double range = Math.abs(max - min);
+
+ if (labelCount == 0 || range <= 0 || Double.isInfinite(range)) {
+ mYAxis.mEntries = new float[]{};
+ mYAxis.mCenteredEntries = new float[]{};
+ mYAxis.mEntryCount = 0;
+ return;
+ }
+
+ // Find out how much spacing (in y value space) between axis values
+ double rawInterval = range / labelCount;
+ double interval = Utils.roundToNextSignificant(rawInterval);
+
+ // If granularity is enabled, then do not allow the interval to go below specified granularity.
+ // This is used to avoid repeated values when rounding values for display.
+ if (mYAxis.isGranularityEnabled())
+ interval = interval < mYAxis.getGranularity() ? mYAxis.getGranularity() : interval;
+
+ // Normalize interval
+ double intervalMagnitude = Utils.roundToNextSignificant(Math.pow(10, (int) Math.log10(interval)));
+ int intervalSigDigit = (int) (interval / intervalMagnitude);
+ if (intervalSigDigit > 5) {
+ // Use one order of magnitude higher, to avoid intervals like 0.9 or 90
+ // if it's 0.0 after floor(), we use the old value
+ interval = Math.floor(10.0 * intervalMagnitude) == 0.0
+ ? interval
+ : Math.floor(10.0 * intervalMagnitude);
+ }
+
+ computeAxisValues(min, max, labelCount, range, interval);
+ }
+
  /**
  * draws the y-axis labels to the screen
  */

MPChartLib/src/main/java/com/github/mikephil/charting/renderer/YAxisRendererHorizontalBarChart.java

@@ -57,7 +57,7 @@ public void computeAxis(float yMin, float yMax, boolean inverted) {
  MPPointD.recycleInstance(p2);
  }
 
- computeAxisValues(yMin, yMax);
+ computeAxisInterval(yMin, yMax);
  }
 
  /**