Update CHANGELOG.md, bar_chart.md, and line_chart.md

CHANGELOG.md

@@ -3,6 +3,7 @@
 * **BUGFIX** Fix LineChart width smaller width or height lower than 40, #869, #857.
 * **BUGFIX** Allow to show title when axis diff is zero.
 * **IMPROVEMENT** Improve iteration over axis values logic (it solves some minor problems on showing titles when min, max values are below than 1.0).
+* **IMPROVEMENT** Add `baselineX` and `baselineY` property in our axis-based charts, It fixes a problem about `interval` which mentioned in #893.
 
 ## 0.41.0
 * **BUGFIX** Fix getNearestTouchedSpot. Previously it returned the first occurrence of a spot within the threshold, and not the nearest, #641, #645.

repo_files/documentations/bar_chart.md

@@ -31,6 +31,7 @@ When you change the chart's state, it animates to the new state internally (usin
 |borderData| check the [FlBorderData](base_chart.md#FlBorderData)|FlBorderData()|
 |maxY| gets maximum y of y axis, if null, value will be read from the input barGroups | null|
 |minY| gets minimum y of y axis, if null, value will be read from the input barGroups | null|
+|baselineY| defines the baseline of y-axis | 0|
 
 
 ### BarChartGroupData

repo_files/documentations/line_chart.md

@@ -31,8 +31,10 @@ When you change the chart's state, it animates to the new state internally (usin
 |borderData| check the [FlBorderData](base_chart.md#FlBorderData)|FlBorderData()|
 |minX| gets minimum x of x axis, if null, value will read from the input lineBars |null|
 |maxX| gets maximum x of x axis, if null, value will read from the input lineBars | null|
+|baselineX| defines the baseline of x-axis | 0|
 |minY| gets minimum y of y axis, if null, value will read from the input lineBars | null|
 |maxY| gets maximum y of y axis, if null, value will read from the input lineBars | null|
+|baselineY| defines the baseline of y-axis | 0|
 |clipData| clip the chart to the border (prevent drawing outside the border) | FlClipData.none()|
 |backgroundColor| a background color which is drawn behind th chart| null |